: : : When used as a cutting weapon a straight - double edged sword hacks like an axe into wood, this can also give devastating wounds, but only if the sword is heavy-bladed, in turn this weight cuts down on its maneuverabilty. The big advantage of the straight double edged sword is that it can be used both to cut and thrust. The thrust is the surest way to kill quickly, if delivered correctly. However, a thrust, if it doesn't hit the mark, results in you being over extended and wide open to your opponents riposte cut.

: : Most swords of the middle-ages and renaissance were actually fairly light (generally 3lbs or less), and not particularly blade heavy at all (indeed they tend to be extremely well balanced), yet artwork of the period shows them capable of inflicting horrifying wounds and this is confirmed by archeological evidence. As to the effect of the blow versus the thrust some historical masters of defence say that the blow is surer than the thrust (for example George Silver in his 'Paradoxes of Defence' circa 1596; though he does say that there is no true fight with out both the cut and thrust).

: Well there's light and light, try swinging one around for a few minutes! Early Mediaeval European swords had relatively wide and heavy blades which were best used for the cut. Later weapons (after plate armour appeared) were more tapering and optimised for the thrust, though bastard or hand-and-a half swords were still used for cutting, but these retained the ability to make effective cuts by sheer size.

I have engaged in various forms of sword combat, both armoured and unarmoured, with steel, wasters, boffers, schlagers, and foils for nearly twenty years and spent several years studying a Japanese style as well. Granted the swords of the early medieval period (ca. 500-1000 AD) tended to be shorter (28" give or take),
with wider blades more suited to cutting, these were often suprisingly light (1.5lb or so). During the middle period (1000-1250 or so) the sword length increased to about 3' and while typically a cutting weapon and useful against the armour of the period (leather, chain etc), those that were capable of thrusting are not unknown. After this period the sword length increased and they were commonly capable of both the cut and thrust yet still remained much lighter than is commonly believed.
Two excellent resources on this subject are 'The Archeology of Weapons' and 'Records of the Medieval Sword' both by Ewart Oakshotte.

: The controversy between advocates of the cut or the thrust raged in British army cavalry circles for over a century from the Napoleonic period.

: The pros and cons can be stated as:

: Pro Thrust:

: Useful in first clash, in a charge.

: More often fatal than a cut if delivered correctly.

: Con thrust:

: Is not as instictive an action as the cut.

: Needs more instruction.

: Has to be aimed at the torso or head to have any hope of being successful.

: Is more easy to deflect or parry than a forceful cut.

: A missed thrust leaves the soldier over-extended and wide open to a counter-cut.

Perhaps with an overcommited lunge such as is traditional in sport fencing. But the thrust was not likely to be used in that manner with a medieval sword. A soldier missing with an over committed cut will find himself in a similar situation. When used properly even if you do not hit your opponent you will remain gaurded whether you cut or thrust.

: Pro Cut:

: Is an instinctive way to use a sword, frightened soldiers in melee tend to cut even when equipped with swords optimised for thrusting.

: Cuts can be confidently aimed at any part of the body, a soldier with a wounded arm is effectively as useless in battle as if he had been killed.

: The cut is more easily recoverd from than the thrust. That is the missed cut can be converted into a block more easily than a missed thrust.

In my experience I have not found one considerably more difficult than the other to recover from, if the attack is properly applied. Blocking an attack with your sword is a 'last resort' manueovre. More common in extant historical treatises is avoiding the blow and countering; and to bring this back on topic: that is how Fingolfin fought Morgoth (at least initially).

: Con Cut:

: Cuts are usually less liable to be fatal.

Often a cut with a sword will render a person more immediatly incapable of fighting than thrust. George Silver in his 'Paradoxes of Defence' (ca1596) says that he has seen several
encounters where one person had been thrust through several times and continued the fight, but no one continued after a receiving a solid cut which would commonly shear the limb away.

: Not as effective in the charge, as the horse's forward momentum contributes little to the force of the blow.

A trained warhorse and cavalryman would act in unison whether the cut or thrust is used. It is my understanding that the charging warhorse would contribute significant weight to a blow.

:
: : : In war the curved sword would have the advantage in melee conditions, though the straight sword would be more useful in the first clash, when opponents are at arms length. This is particularly true of cavalry charges where a straight sword thrust can make use of a locked wrist to allow the impetus of the horse's motion to be directly used.

: : I tend to disagree that the curved blade would necesarily have the advantage in melee. I am interested in why you think this so.

: Partly instinct, from wielding different sword forms, and partly historical from the debate I summarised above.
: If one ignores the effect of armour, then the advantages I have listed for the curved sword make it the more useful in the chaos of a close melee. A curved sword is more maneuverable and can be swithched from one side of the body to the other more easily (especially if there is a horse's head in the way). I don't know if there is any physics behind it, but the curve of a sword seems to add impetus to the cut, the sword feels like it wants to cut, which isn't the case with a straight sword.

I agree that a sword intended soly for cutting such as you are describing may cut more naturally than a sword not so designed, but in my experience I have not found one form to be remarkably more manuoevrable than the other. Of course this may also have to do with how a warrior is trained and what type of weapon he is most fammiliar with.

: I have two swords one straight (a French cuirassier model) long, with a relatively narrow, tapering double fullered blade with a spear-tip, and a curved one (British light cavalry sabre 1796 pattern) with a very pronouncedly curved broad blade with no real point. The French sword is elegant and comes to "the point" really easily, but it feels like it wouldn't do much damage if you cut with it. The British sword, though heavy, has a shorter blade and curve which makes it more maneuverable than the other, and it feels like you could cut down trees with it. I would, if my life were dependant on it, much rather have the curved sword than the straight.

The French cuirassier model, as you describe it, should feel like it it would do little damage if you cut with it as it seems from yuor description to be intended solely as a thrusting weapon. (I think I know the style of sword you are writing of.)
Of course JRRT probobly did not envision his characters with either of those types of swords.;)
I have and have had a variety of swords myself.:)

: :
: : : Further, if the enemy has well-made, effective armour the utility of the curved sword is particularly reduced as the armour-piercing ability of the thrust is much more effective than a cut from even the sharpest sword.

: : Of course even more use against a heavily armoured foe is the Axe such as the Sindar and Dwarves preferred, or the mace, hammer and other impact weapons.

: : : All this said the cut is the more instinctive way of using the sword, and the effective use of the thrust requires more skill and training. Perhaps the bad guys were less skilled warriors, in general, than the good guys?

I tend to agree with George Silver (cf) that there is no true fight with out both cut and thrust. To use either effectively, in a combative situation, one must be well trained.