[1.2.378] Magicians in Jump

Umm what? I don't see I/L gaining much at all.

Buff Mastery is removed, so bye bye to 30 Magic Attack. That will cut damage by 10-15% right there.
Infinity bonus cut in half. Edit- actually more than half, since it benefited from buff mastery duration extension I believe.
CL will be slightly faster, but same total strength as before. Will the speed increase make up for the above losses? Doubtful.
New skills are interesting, but I won't affect bosses.
Am I missing something?
I don't see myself de-mothballing my AM for this.

Fair enough that you feel that way, but they got glacial chains skill and a freezing big bang out of the deal with a faster c/l that already hits more than once per mob.
Yes I would say you missed something.