Re: Question about the maths behind attack roll and defense rolls
 

True enough. Part of the problem is that players who come from games where the only results are "did damage" and "didn't do damage" get bored if nobody loses HP. Ironically, reducing fights to "Whose HP get depleted first?" is the most boring of all combat models. GURPS is nifty in that even during prolonged exchanges where nobody loses HP, there are thrills and chills when the fighters' choices lead to near things (like making that Parry roll of 9 exactly when somebody swings an axe for your neck), and plenty of nondamaging effects: feints, FP spent on extra effort, falls (esp. during kicks), dropped or broken weapons, ground lost to someone whose attacks demand retreats and who always steps after attacking, etc. Also, there are lots of choices; you don't just roll to hit over and over, but can pick targets and techniques, select what defenses you use, etc.

I think the easily bored HP-counters might be more engaged if they had tracks to show not just personal HP, but weapon and shield HP, FP lost to extra effort or chokes, current defense penalty vs. each foe thanks to footing and enemy feints, current defense penalty of each foe thanks to the same in the other direction, current movement point cost due to footing and posture, etc. Making one's enemies' tracks worse and/or one's own values better would be meaningful even if it wasn't just the HP track all the time. Lots of gamers seem not to appreciate the value of "he's kneeling, with -2 to attack and defend, and triple movement cost" or "he's against the wall and can no longer retreat for +3 to Dodge," and rarely seek alternative victories like pressing the foe so hard that he uses up all his FP on Feverish Defense and falls over, or just disarming him and using Intimidation.

Re: Question about the maths behind attack roll and defense rolls
 

I tried quick contests, to speed things up. It speeded them up alright - first strike wins. Nice for the PCs, until they met faster NPCs. Something to use for PCs to wipe out waves of mooks; perhaps use MoS as a measure of time.

Better to stick with the RAW. Although, if your combatants are a pair of unskilled neophytes using Average skill at default, doing something to shorten the combat is tempting, unless you actually want 20-40 rounds of miss-miss, miss-miss, miss-miss*, Hit!-dodged-miss, miss-miss, miss-miss, miss-miss, miss-Hit!-dodge fail-(d6-2?! 1HP injury). Then again, even skill 5 can give you a critical hit on your first roll and that could be the fight over.
*statistically, you should multiply the miss-miss bits by 6... Better yet, get them to use their brains (IQ check: evaluate for +3, AoA det+4, Mighty Blows...)

Re: Question about the maths behind attack roll and defense rolls
 

Though those effects tend to be either fight-ending or extremely transient. In general, the advantage of a hit point system is that it makes combat relatively predictable (you don't have people flattened by a single bad roll, and a GM can know that a specific fight is highly likely to be challenging but beatable) and means you can pretty much tell you're winning (or losing) before anything too dire has happened (and, if you're losing, perhaps break out your Special Tricks, or whatever).

This isn't realistic -- realistically, random bad luck gets people killed in combat all the time -- but IME players don't really want realism.

Re: Question about the maths behind attack roll and defense rolls
 

Well, maybe D&D players don't or something . . . it seems that lots of GURPS players do. Problems arise when a GM who likes GURPS and realism decides to run a game for players who mostly don't share his views. It cuts the other way, too: I can't really have fun in a game where there's no chance to win with a coup; few choices other than "attack," "strike harder but not so accurately," and "use Special Trick of the Encounter/Hour/Day"; and no active ability to evade harm when my enemy hits me. Or to be precise, I can't have fun with that in an RPG. It's fine for computer games; indeed, computer games can do that so much better than RPGs can that I don't see the point of that kind of game on a tabletop.

Re: Question about the maths behind attack roll and defense rolls
 

Well, yes, though there's a selection effort there; you're more likely to play GURPS if you like the way GURPS plays.

Side Note: I actually rather like GURPS combat for some genres, but it's a taste I don't really see my players matching. Then again, I think I've run more TPKs than the rest of the people I've played with put together.

Re: Question about the maths behind attack roll and defense rolls
 

If i recall correctly, "Deceptive Attack" was developed either here in the forum or on the GURPSNet-l Mailinglist under the name "Trade accuracy for effect" (TAFE) already before the Compendium Version :)

Re: Question about the maths behind attack roll and defense rolls
 

Oddly, I had more near TPK's in my only (~6 month) D&D 3.5 game then I've ever had in decades of GURPS.

Re: Question about the maths behind attack roll and defense rolls
 

It couldn't have been here (might have been the Pyramid fora, which existed before and then alongside these), since this forum didn't exist before the Compendium.

Re: Question about the maths behind attack roll and defense rolls
 

I didn't say I'd only run TPKs in GURPS. In fact, I'm not sure I've run one in GURPS. I just tend to run games that push PCs limits, and when you do that every so often they fail.

Re: Question about the maths behind attack roll and defense rolls
 

Also, if combat isn't risky, characters can't be heroic in risking their lives for that which they believe is right.

And that's a loss.

It can also easily lead to a lot of random fighting, because fighting isn't dangerous. There's no encouragement for the characters, especially the on-stage characters (the player characters) to pick and choose their fights. I don't like a lot of combat in RPGs, I'd rather see a few important and exciting fights, than a lot of unimportant and routine fights.