20 and 40 man stutter
Version v3.160-vanilla-classic
ive noticed a slight stutter when using VuhDo (seems to be a recent thing) its extremely bad on Sapphiron with massive frame drops. other raids its not bad just a slight stutter with 10 fps drop for a split second. can confirm its Vuhdo as ive disabled every addon and worked through them all.
not sure of any other information that would help.