Single Comment

> We may be coming to agreement on one aspect of the first question,
> that its small board size affects FIDE's 1st move ad.
> The 16x120 and 8x80 boards have pretty much settled that, no?
> Any objections?

Well, I am not sure how you consider it 'settled'. In 16x120 Cheiftain I
am prepared to believe there is no firs-move advantage. For 8x80 FIDE I
think the advantage persists, because letting he opponent advance would
give him he advantage of being closer to promotion, even when he is still
completely out of range for hostilities.

> Promotions need to occur reasonably fast to be of value.

No, why? In FIDE promotions can (and usually do) decide games in the
end-game. Like in KPKP or KBPPKNPP. Who wins in a Pawn ending is usually
decided by who's pawns are most advanced (promotion races). He who Queens
first simply uses his Queen to block, and hen gobble up the opponent Pawn.
Just being there one move earlier is completely decisive.

> On the second question, is it possible that black's skipping
> one turn in Chief does not seriously - that is, do something
> like give white a 30% win advantage in games that are not drawn - 
> affect black's winning chances? Is it possible that with a one or
> even two move advantage, white only wins 20% more, or even 10?

Yes, of course that is possible, or even expected. In FIDE the first-move
advantage is only 3% excess score, so one tempo (the difference between
being white or black) is only 6%. So numbers like 10%, 20% or 30% are
really unheard of. They are in the range of having a one or two-pawn
advantage, so that a single move is not even worth that much in the
presence of hanging pawns.

Of course I don't know what the advantage in Chieftain Chess is for having
an extra commoner. (And I would be surprised if you did...)