I seem to be having difficulty being clear. I'll try.
I believe there is some merit to capture area in general, but it isn't all there is.
I don't think element thickness as in thin or thick wires/tubes represent the discussion of capture area. I simply said thicker elements affect bandwidth in response to a question about width as that is the only width with consequences I could think of. When I think of capture area I think of differences as in overall physical sizes, ie 1/4ƛ, 1/2ƛ, 5/8ƛ, 7/8ƛ, or significant differences between the sizes of mobile vs base antennas. I could be wrong.
Maybe someone will be interested in defining the parameters of a test that eliminates the inherent advantages of larger antennas in the real world, but not likely.
In the time I've been here the debate over the right and wrong way to test/model/compare, and to drink from a cup have been debated to the point that we all know everyone else who does not hold our exact point of view are undoubtedly escapees from the local mental asylum. 
Some think it has already been discussed . . .
Do the laying down models and see if it makes a difference.
Then we can still read what folks are actually experiencing with their antenna systems as they are running them at their QTH.
One thing I do suspect, all the trying this and/or that GP arrangement, and this or that height, and this and that tuning network that you and I went through with the EFHW I made has resulted in giving me a little antenna that seems to perform better than either my previous A99s, or this one before experimentation.
So, I think enough tinkering and fine tuning and adjusting, and tuning some more can make a difference in an antenna set up from the box and the same with a patient dialing in over and again at the same location. Unfortunately, most folks want something that is so simple from the box that there is no possibility for any fine tuning. Without the 259b I couldn't have done it. These things take time, and tools. An antenna lacking movable components would likely not lend itself to finer tuning, buy and fly types like Imax2k, A99, GM, - tuned from the factory types.
I look forward to future fun and frustration with these things.
