Its all about efficiency. You can find a million posts titled "what's the minimum poundage to hunt XXXwhatever". The meaning is clear but, the real question is what is the minumum recommended arrow momentum.
If an efficient 45# lb bow system gives the same momentum to the same arrow as an inefficient #55 bow system, then the only thing the 55# does better is keep that achy shoulder complaining.
When i got burr in my rotator and had to lay down the #55, I got a modern RD bow, a Dryad Windtalker u-finish blank. I'm pulling about 43#@27 and with a 6 strand skinny string, whisper quiet launch of extreme fwd of center 13gpp arrows that fly straight like darts and tipped with razor sharp single bevel 2 blade Tusker Concordes -- well, my confidence is up, come on October.