In all honesty, it hasn't dropped off a bit for Elk or deer. I got lucky the first year, made a bad shot on a bull, but still nicked a lung and was able to sneak in close to finish the deal. the rest of the time the kills have been mostly good and consistent.
It sure isn't as quick and easy, but thats the point I suppose. I'm a better hunter as a result and theres no doubt my consceince is cleaner. Also, more emotion goes into the whole process. Taking the life of an animal is now a rite, an exchange, a handshake.
Now, for antelope, I haven't been able to tie the knot, spot and stalk, since my switch. Waterholes fill the freezer there. However, I much prefer to stalk them. I have missed, flat out, 6 goats in that period, of 4 years hunting antelope (a bunch of years in there, since starting, I didn't have time for goats). most of them ducked, two of them got lucky as all get out being saved by ghost peices of brush.
In other words, in all cases, it was my fault.
Spot and stalk antelope is my nemesis right now, its been 8 total years since I killed one not at a waterhole. This year will be the year!