I do it a little differently...

I could have a shot out to 150 yards, so I sight in 2 1/2 inches high at 100 yards and I'm 3 inches low at 150...This is as far as I plan to shoot, so I just hold for a high shoulder shot at 150...Now, this is the important part, from 10 yards to 125 yards, I just hold dead center of the shoulder and pull the trigger...

Sighted in 2 1/2 high at 100 is only about a inch and a half high at 50...

Now, you might not want to go as high as 2 1/2 high at 100, but I'd go an inch high at 100, just in case you see one at 125 and hold for 100...With your gun sighted in a inch high at 100, you'll never know the difference at 50...