LOL.
Since you are -- what? -- near 6', and admittedly have monkey arms?

-- I'd have to guess you are mostly ectomorphic. I've seen your permabulker pics. You were decently strong by any of my estimations, especially if you were inclining 315 for full-range reps and/or pulling 600 from the floor. (Aside: I have a long memory, and those lifts would not have made you the strongest person at UNC Charlotte

smiley-et cetera.)
But even when you were in that mode, I didn't see insane endomorphic tendencies. Yeah, you were "fat" and all that shit, but serious lifters could still tell you were among their ranks. It's not as if you were some blob kid in a high school weight room who did a quarter squat with 675.
I digress.
You yourself say you're much better at lower reps on bench press.
Why, then, are you trying to be something you're not?
It is not as if you are some semi-strong HIT guy who, after years of single sets to failure for an exercise or two/bodypart, suddenly decided to "try" volume.
If that was the case, I'd instantly understand your problem; after all, it used to be mine. In spite of all the shit we hear about HIT-oriented methods here, the ones I used got me very, very strong and in impeccable form. None of that 4 seconds up, 4 seconds down bullshit, but I did do some nice benching triples with each rep paused on my chest, and I was also proud of my Pendlay rows. Hell, I was even proud of a few of my Hammer Strength moves
I would've thought you were made for moderate strength over a "distance," but when it comes to pressing, you obviously are NOT, Adam.
So, why not embrace something better suited to your physiology? Nobody says you have to go my route and follow a low-volume routine; there are, as the saying goes, many ways to an end. Why not try something more along the lines of 5x5 or 3x3? If you're concerned about pec development, do as someone else suggested and pre-exhaust with an isolation movement first. I played with that in my early days, particularly with Nautilus equipment. The results were generally good, especially for the back machines. Their Double-Chest machine was always too wonky for me; I could "press" the stack on the thing forever, but the fly/cross portion was so awkward I practically had to stand up to finish a single rep with just a plate or two on the stack :|
The old lady is bugging me and I digress again. Do what you do best, plus a bit more TUT/set. And don't fucking overtrain so much.