ok but just my opinion....didn't mean to offend. tbh i have never had a problem with even two year old entires being a problem (even ID x's) but i do a LOT of groundwork first. I'm not a fan of twitching with ANY horse, especially not a baby. Also be aware that being a entire at his age makes him no different to any other foal, sometimes if entires are given a precident because they are still entires that in itself can cause problems.
i have done alot of groundwork with kaiser too, some horses are just a bit more spirited than others