hello
just do thorim on ulduar in the beta, don't have anymore the problem in the corridor during combat. Don't try if it's new or already in 5.4.8 but for me, thorim corridor and yogg saron sanity are a problem for soloing mount
EDIT : no sanity problem for yogg saron 25 but you need 2 more trashs to kill sara in P1 (she stays at 45k and don't want to die after the 4th) and the passage to the brain doesn't open when you kill all the trashs in the room before the brain so yogg unkillable for the moment