You determine a comfortable draw weight in the same way you determine a comfortable pair of boots. Would you try to force yourself into an expensive pair of boots hoping you'll stretch into them?
Just as you want to try boots or shoes on late in the afternoon when your feet have swelled, consider hunting conditions where it may be cold, you may have on layers, you may be shooting at a more odd angle or from your knee's, etc.
Don't determine a peak weight in the Summer when you're standing flat footed in a tee shirt on a nice 80 degree day. Think about sitting, in 30 degree temps, you haven't moved hardly a muscle in 3 hours and now your cranked up because a spooky deer showed up 15 yards in front of you and the winds just died, leaving the woods dead quiet. Do you want a really easy draw or a draw that's 5 pounds too much for you?
As with boots, can you walk in them all day and still enjoy the day? Now, with bow weight, can you shoot or stump for extended times and enjoy it?
Consider real world hunting situations, not practice on the range. If need be, can you hold calmly at full draw for 10 seconds if you had to do so or would you be shaking? If you can hold comfortably at "anchor" for 10 seconds, and I understand that anchor isn't a necessarily a stopping place but hunting situations often cause quick adjustments, then you should be in good shape.
For my style of natural ground blind hunting, I have tons of brush in front and behind me, with just a small "window" for the shot and I draw and hold just as the deer is entering the "window" and then shoot when the deer has walked into my "window", while I'm at anchor. I shoot very short range and light weights and it's proven very successful since I completely stopped hunting from treestands. The only year I haven't shot at least one deer doing this, since going exclusive on the ground with trad bows, is the year I had shoulder surgery.
I understand that this approach my not be typical, but for consistently putting lots of deer in the freezer, I've found it more effective than a typical "snap" shot. With lower weights, this is easy to do for me, with my shoulder issues.