A nifty question on the GURPS Forums about fighting with a one-handed spear.
On the one-second time scale of GURPS, the grip change needs to be handled with higher resolution.
When I fight with a one-handed spear in my viking martial arts class, shield in the other hand, I use a sliding technique to reach out. I thrust with the spear, and let it slide in my hand until it reaches the bottom of the haft. I then have to yank and recover it back (Ready maneuver). This is with an underhand grip, which is my current preference because I haven’t trained up overhand yet. I hear good things about it. The sliding technique works there too, though.
Basically, you thrust with the spear and “throw” it, sliding in the hand to the limit of the spear range, typically about 6 feet. When it hits or gets as far as you like, you re-grip. Typically the spear is then over-balanced and way the hell out there. When that’s been done to me, I’ve occasionally knocked down (parried) the cast spear and then stepped on it, to take it out of play. Defender is forced to drop it and draw their seax, if they have one.
The “anyone can play” resolution that does the least violence to the rules would be to just allow anyone with training in spear to do it, but the attack causes the weapon to become Unready. A technique at Spear-1 might do it (I think it’s easier than Armed Grapple, which is at -2) and still be able to be bought off with a 1-point perk, which feels right.
This gives you Reach 2 at the cost of having to re-ready. If that one-point perk allowed you to fast-draw (spear) or Spear-4 to recover as a free action on the next turn, that would not bother me at all.
Another way to go would be to model it as a Committed Attack that is Determined and uses the “attack and fly out” option, but with a 1-point perk that lets you basically attack at full skill to Reach 2, *without* moving your feet and actually attacking and flying out in time-of-the-body.
The penalties to defense (can’t parry with the spear) make complete sense in this case, and the fact that you actually are back to Reach 1 at the end of your turn without a ready is a bit cinematic, but it’s awesome. In my experience, the sliding attack takes a turn, and then you recover the weapon on the next.
Dungeons and Dragons
Eh. With the six-second turn of D&D, you can do all of the above multiple times in a turn. The simplest way to do it would be to allow an attack to higher reach, and then recovery to low-reach as a bonus action. Or just assume all of that sliding is below the resolution of the rules, give even a one-handed spear Reach, and have done with it.
I’ll have to check to see what I did with Martial Spear Fighting in the Dragon Heresy manuscript. Make sure that the Reach change is both allowed and as simple as possible.