I know Yoda was prequal era. This is very, very obvious. What I am saying is Yoda at a younger age MIGHT be able to beat Jacen. (I hate the name Caedus.) This is one of those "what if" fights. As powerful as Jacen was I am not 100% sure he could handle a younger Yoda. Maybe he could, who knows? I still think it would be a draw. I honestly cannot say who would win.
No he wouldn't.
Yoda in his prime was prequel era. Confirmed by Leland Chee in his statmeent about fighting against Palpatine.