Even if they do start, I wouldn't draft them. I'll dig up my keeper drafts from the past and rarely do you strike gold with rookie hitters drafted and held. Just looking at 07 for instance, Delmon and Gordon went top 10 in my keeper league. Braun was not drafted and Tulo, due to his slow start, was dropped by the original drafter.
Rookie pitchers are a whole different story. I drafted and held Prior before he even threw his first pro pitch (I was very confident that he would make it) as well as Lincecum last year. I'm targeting several rooks at the draft.
I think the problem is not rookie hitters, but which rookie hitters people grab. I had no problem grabbing Wright and Butler as soon as they came up or drafting Utley. I didn't grab Delmon or Gordon, because I didn't think either was ready. I really would not call Young a bad pick in a keeper league. Even Gordon's performance is hardly a killer bad pick. In a keeper league, you can't even really base your evaluation just on that year.
Braun was not drafted in nearly all leagues because he started in AAA last year. Tulowitzki was grabbed in round 13 of my league and is still with that team. I was hoping he'd fall to later rounds, because I would have grabbed him. Don't know what that says about the leagues we play in. Chris Young (Round 11), James Loney (19), Pedroia (22) all seem to have been good picks. Worst picks I recall from last year were Iwamura, Dukes, Wood and Ianetta.
Compare that to this list of 2007 pitching prospects. Many of them were drafted last year. Other than Lincecum and maybe Gallardo, did any of those guys provide comparable value even to Gordon last year, much less to some of the better hitters?
http://fantasy411.mlblogs.com/mlbcoms_f ... ng_pr.html