It's probably just bias against trainees in general, since you have to train them up to be useful, and the lowturncount players aren't very interested in that sort of thing.
I'm a low turn-count player; Ross hits hard enough initially and comes early enough that it is not hard to force him to get kills. Turning him into a Pirate allows you to use Garcia alongside him, as Colm (sadly) falls out of being useful faster than Matthew in FE7.
