Yeah, you could have 70 lbs limbs put on and then back-off the weight to around 60 lbs. Keep in mind though, the farther down from max poundage you take a bow the louder it becomes.
In the world of archery, speed and noise go hand-in-hand. I like to keep my set-up shooting as fast it can, however no bow will (as of today) will shoot a "hunting arrow" faster than the speed of sound. With that in mind, I always go for a quieter bow.
My bow is a 2005 Pearson Dagger, 27 1/2" draw, 60 lbs., with arrows over 400 grain. Last year I chronographed the arrow at 245 fps. So far, I have had pass throughs on 1 caribou at 35 yards, 1 cow moose at 28 yards, and 1 bull moose at 61 YARDS! I also burried an arrow deep into the spine of another cow moose at 35 yards and she dropped right there.
It's all a bunch of trade-offs. Here I need arrow weight (so I get a quieter bow too), when I go back to the lower 48 and start hunting deer again, I'll want a faster arrow.
Good luck and keep flingin' arrows, KP.