Bob,
I can only speak from my experience, but I have caught bass in 22' deep water during the summer with stumps on the bottom and a hump to the side being the only structure. However, that was in a 60' deep reservoir - not a pond.
Surprisingly, we would frequently catch 10" spotted bass on 6" plastic worms while fishing that area for large LMB. Apparently, even the small bass congregate on deep structure.
Sunil makes a good point about oxygenation. If the deep water in your pond is anoxic, then it will not hold any fish!
For a 2-3 acre pond, will you have water flow through for much of the year? If so, you could have some deeper, oxygenated water by constructing a bottom drain for your normal pond outlet. If you have a significant amount of water coming into the pond, and you pull the most oxygen-depleted water out of the pond via your drain, then you could sustain some deep, habitable water for the fish.
***One caveat, you would also be draining the COOLEST water from your pond (for most of the year). That could be detrimental to a Texas pond in July and August - but there are lots of variables. If you did install a bottom drain, then I would be sure to install a valve and a way to switch to a surface drain.
