Dear John and Mark,
1. You are right about induced drag being inversely proportional to Vsquared. Aslip of the pen
2.I still maintain that cg can be significantly behind wing cp because one purpose of tailplane is to make wing+tail cp behind cg,thus ensuring static stability. In such a case, for trim,tail lift would have to be upwards.
However, if you wanted the wing cp to be behind the cg, then the trim load on the tail would be downwards (I hope I have got that the right way round---I am sure somebody will tell me if I havn't)
Keith