But I guess that's my question...what criteria does one use to determine which skill is more appropriate for watercraft? How would the campaign setting change which skill is more appropriate?
Question #2: Spin...as I understand it, per the Spirit of the Century book, a successful defense against an attack roll by 3 or more Shifts allows that defender to grant/impose a +1 bonus or -1 penalty to the next roll made by anyone in the scene (be it ally or opponent) or may be treated as Overflow for a Supplemental Action (pp. 79-81). What if the defender successfully defends by 6 shifts? Does the bonus/penalty increase to a +2 / -2 Spin? In other words, is Spin a plus/minus 1 for every 3 Shifts?
Question 1:
In my experience, the answer to your question is based on some other questions, and would be campaign-specific. The questions I would consider would be:
1) How important is watercraft to the campaign? (If the campaign is set on the 7 seas, or was about pirates, then I might add watercraft as a stand-alone skill.)
2) Is either Pilot or Drive a skill that -needs- more trappings to equalize its usefulness?
3) Which skill's activities, Pilot or Drive, most closely approximate the activities that you foresee occurring with 'watercraft'?
4) Would it make sense to have Drive -and- Pilot assist in watercraft operation when appropriate? i.e. Driving a speedboat is similar to a car, and a luxury liner more similar to an airplane?
5) Would it be a better choice to allow boat/ship operation via a stunt, rather than a skill or trapping?
Ultimately, the answer to your question resides with you. FATE implementations generally go out of their way to value a lower number of skills that are more broadly useful, rather than a high number of skills that are more granular. This, I believe, reflects the general design philosophy of FATE that "heroes should be pretty darn competent". You, as GM, need to feel that the skill fills a needed niche, and accomplishes something that furthers the game. Your players need to feel the same thing, and if you find a skill consistently not being taken/used, then that is a red flag that it might be improperly balanced.
For my money, in my pre-WW1 game in development, I have a version of Watercraft that is a stunt, applicable to Drive or Pilot when appropriate. But that was just for my game, based on my 'read' of the campaign.
Question 2:
My understanding of the rules is that spin is one and done. Achieving multiples of spin does not convey an escalating +/- bonus. That said, I don't see running it the other way as being unbalancing, and you could certainly try it out to see how it plays.
"Spin" is replaced by "Boost" in the coming Fate Core, and since a Boost is a temporary Aspect it will always convey a +2 to the character's use (and it is a one time use).
I recommend that you frequent the Fate YahooGroup [
http://games.groups.yahoo.com/group/FateRPG/] for a stand-up bunch of folks who know FATE inside and out, and are willing to take on any question.
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Be seeing you...
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