After trying big rungs a few times they do not give the same gains that i am making from the 3/4 inch in terms of finger strength. However, you are doing doubles where as im still doing taps and ladders.
How're you quantifying your finger strength gains? If it's by watching how many sets/reps you can complete for this training method, how're you controlling your experiment for improvements in technique?
It may (may!) be more accurate to ignore the first two or three weeks of the training (perhaps even a month), during which time you're putting together better technique for it. An activity like campusing rungs has much less technique available to be learned. Therefore, it seems logical that one would reach the point where muscular gains outpace technique gains much more quickly than actually climbing.
During the first few weeks, I think your body would still be making gains in places other than your fingers (technique, tension, etc), and since your goal is to measure finger strength while attempting to control for other gains, you might want to perhaps throw out the first few weeks.
Perhaps you're already doing this.
You've gone into this with the idea that you're going to be flamed. I'm not flaming you. I'm curious.