The Caithe transform is poorly implemented
Same problem as for the downed state and it is as frustration in both cases. The Caithe fight were so much easyer on my warrior run than on the ele playthrough that it is not even funny.
Halas I feel that it is a limitation of the engine about transforms. Why did they have that whacky idea of so big a difference in base vitality anyway. It also makes balancing ele thief and guardian so hard in PvP.
Cheers
No idea why they did such a huge health difference, but it has consistently messed up the profession balance in the Living Story. Hopefully they address it in the expansion.
Also, Anet, next time make sure your transform cannot teleport and get stuck in the walls, roof and objects, and Caithe does while stealthed.