Does the surgery skill come into effect only when the character that has it is in the field of battle? (assuming he/she is the only one with the skill) I ask because at the moment I have to make sure that my medic with the surgery skill, Jeremus, stays way at the back of each fight. Unfortunately sometimes some enemies manage to reach him and knock him unconscious at which point the effect stops, which is bad :P I'm guessing the answer is yes unfortunately, but I'm hoping I'm wrong. It's especially a pain to keep him out of harm's way while defending a siege against 600 enemies :P

AFAIK, the surgeon has to be in the party, not in the battle itself. And he must not be injured (he has to have more than ~15% of max HP).

I'll add a couple of notes which took me a long time to find out.

....

The characters I want to stay alive through the fight. Ar them with as heavy armor as they can wear, as fast horse as they can ride, and only a ranged weapon. Doesn't make them super effective, but at least they avoid melee then. Also, have them on the very bottom of the party pile.

... edited out the bad info which took me a long time to learn

Then I'll also add a small note to this. Party skill value is calculated like this: N+B=X; where N is the surgery skill of the best concious surgeon in your party (either your or companion's), B is bonus (see lower) and X is the final value.

The bonus is based on YOUR value of the skill. (E. g. if you have surgeon skill at 6, party skill bonus will be 2).

0-1 (+0)
2-4 (+1)
5-7 (+2)
8-9 (+3)
10 (+4)

For example: Jeremus has surgery at 8 (and he IS concious). You have surgery at 4 (and you ARE concious). Your party's surgery skill will be at (8+1=) 9, which means you'll have 61% chance that your troops will only fall unconcious instead of death.

+1

Lol. Guess I'll have the hang of warband machanics pretty much around the time Bannerlord comes out.
I think I tired a skill of 4 and only still had the +1, deducing there's no further bonus than that.

Does this mean that if you have surgery 10 - the game calculates X as (10 + 4) = 14?

... edited out the bad info which took me a long time to learn
better answers down there.

Yes, according to the manual that is how it works:

Sorry, Jarmo, but Matewis is right. Bonus is ALWAYS calculated from you, so if you have 10 in any party skill, value of that skill will be 10+4=14, even if you have no companion with that skill. And yes, it goes above 10, with 14 being the max party value (if 10 is char's max). (Else it would have no sense to proceed after 8, because at 8 you'd have 8+3=11, which would round to 10 already.)

I'll take a screenshot in a moment so you will see it.

EDIT: Here (Native Warband 1.158; used experience cheat - CTRL+X):

Highest personal value (of either Me or Rolf) + Bonus (based on Me) = Party total

Wound Treatment ----- 10 (Rolf) + 2 (bonus, based on Me) = 12
Surgery ------------------- 10 (Me) + 4 (bonus, based on Me) = 14
First Aid ------------------- 8 (Me) + 3 (bonus, based on Me) = 11
Tactics --------------------- 2 (Rolf) + 0 (bonus, based on Me)

Hells bells. o___O

I've always been somewhat irked at party skills being less valuable for yourself than nonparty skills - Now, I feel really silly (and even more happy about the design of M&B).

Yeah, it didn't feel right to become an unstoppable warlord without having to put any points into, say, tactics. I don't know as much as my strategist, Artimenner, about it but at least my 5 points spent on it actually contributes :P