Ah i didn’t realise you keep one arm in the BC. I thought you fully removed it.I only dive weight integrated and since I certified in SoCal we were taught to doff/don. It's easy as long as you keep one arn in the BC and do it carefully.. I've used it twice - once in the Kelp - that one was easy b/c I was so tangled I wouldn't have floated up anyway - in a 7/5 suit.
Actually we were taught to straddle the tank if necessary - hold the BC at or below your level - never overhead.
I use a backplate and wing so it’s not really easy to remove just one arm