I've been catching a lot of smaller male bass on the ned rig/TRD so I thought I'd upsize to a bigger mushroom jig and use a big TRD in an effort to maybe target bigger fish.  That theory was not effective.  Still the same 10-15 inch males over and over.  Has anyone had success targeting bigger bass with the big TRD?

I have effectively used them to target bigger smallmouth but it didn't make much difference with largemouth, of course I tried this same theory again and got skunked. 

Same here. The regular Ned is way more effective for #'s of bites, but with no less bigger fish IME.

I have found the Ned to catch more fish, which includes the big girls if they are in the area. My guess is the big fish aren't in the area, because they would eat it if they were there. With a standard Ned I have a 20" Smallie and a few brown trout over 20" on it.