I've had problems with "Y" pushrods too. Lost a nice plane to elevator flutter because the pickle fork pushrod just had too much flex in it. But there's nothing wrong with a Y pushrod setup if you have good straight runs. And the only way to achieve that is to split the pushrod at the other end.

What I do is run two 4-40 pushrods from the elevator halves up to just behind the servo. Cut one here and solder it to the other, wrapped with wire of course. Both pushrods have full length outer sleeves to just behind the fork with supports on each end and more if you can do it. Done correctly this gives two perfectly straight pushrods that have no flex and no intereference problems. Also works with carbon pushrods, just substitute JB Weld for solder.

Dave