"So I guess the question is indeed: do I want to deal with hanging or just suck it up and carry the weight for the sake of simplicity?"
If you are going in over Lamarck Col: I've been that way a couple of times, and there has been no sign of bear activity, nor have I heard of any. Same along the stretch of the JMT from just below Darwin Bench to Wanda Lake. Apparently most of the bears hang out down in Evolution Valley where the pickings are better. Once you get into Ionian Basin you will not be seeing any bears, for sure. Also, you won't see any bears in the Davis Lake area on down North Goddard Creek, up to Martha Lake, or south of Reinstein Pass, IME. Going out over Haekel or Echo, it won't much matter because you'll be within a day of civilization by that time. All of this said, I would not consider the above mentioned stretch of the JMT to be fool proof. If it were me, if I were going without a canister, I'd make a run for Ionian Basin from Darwin Bench so it wouldn't be a concern. Every place else above it is not a concern, IME, and from what I have heard. In the end, you will make your decision based on what you are comfortable with, since you will have to live with the consequences. I hope this helps a little, and that you have a great trip. You are heading into some fine, fine territory.