From my experience I don’t agree with that. I used a pendulum for 2 seasons and I even practiced out of my tree stand with one. 20-25 feet up I was dead on from 10-20 yards with the pendulum slighted in at 15 yards on the ground. Anything closer and I had to aim low. At 5 yards I had to aim about 8-10 inches lower than my impact point.

They do work ok but I switched to a trophy ridge and like it just as well. I could really not tell that much difference than the pendulum when deer were 10 yards or closer when I was elevated. With my fixed sights I am only 2 inches high at 15 yards elevated to 25 feet.

Main thing is that you practice out of your stand elevated so you know your impact point.