Unfortunately we didn't get a final bear for the spring season so no 88 gr data. Bummer because I'm really tempted to take the AR on a hike in moose hunt and a grizzly kill with the 88 gr would have been a good data point.
My thoughts are currently that you are not "dumb" if you use a smaller caliber. But I do think you are getting a smaller sometimes shorter wound channel. I'm comfortable with that on black bears and 7 foot grizzies. If i was guiding and wanted to slow down a charging/escaping 9 footer withsub optimal hits, I could see a real advantage to a bigger caliber with the trade off of more recoil/slower follow ups. As bears get a bit bigger they do slow bullets down More I've noticed.
Currently my "backup" gun is a 308 with heavy handloads of 200 gr ELDX or Nosler Partitions. Seems like a safe compromise because I can work it faster then my 375 and wounds are large.