With all due respect, you are just playing semantics regarding the accessories. To a person who uses a water bladder, the hydration sleeve is not an accessory, but something they require or "need". Granted, terms like these are subjective, I know, but I hope we can agree that it is possible that someone that buys an Ohm might opt to keep all of the removable features and not consider them to be accessories at all. Plus, the Jam also has a removable backpad, so that kind of kills the idea of a "fair" weight of 840g, as both packs have removable features.

And I can just as easily play semantics, if anything for fun. You see, "removable" is also rather subjective. I could argue that the Jam's hydration sleeve is also removable, it is just more difficult. I could cut it off, then later on when I want to use my water bladder, sew it back on again. I could also sew buckles on it and make it just as removable as the Ohms.

So this 84-200gram gap gets all the fuzzier as we nitpick over the details ;)

In the end, I view such a small gap (contrast the weight of Ohm vs. Jam with either one vs. my 1660g Osprey) as not significant enough to argue in favor for the Ohm. The Jam could be modified/trimmed to be around the same or even less than the Ohm, depending on how modified/trimmed the Ohm in question would be. Not to mention, that both bags, based on observations of many seasoned backpackers, generally get two thumbs up. So you take your Ohm and I will take my Jam and let's see what happens. My guess is the same thing: both of us will be happy :)