I can't remeber where I read this atm, but...

It was something about squishier (is that a word even lol) grips, wraps, etc. can aid in hand/wrist issues. Some study that was done on body mechanics. Basically, sub-consciously you grip the softer surface MORE in a effort to still keep a tight grip. The tigher you grip, the more work your hands are doing, more fatigue, stress etc.

I don't know what type of work you do for a living either, but I have some carpal tunnel issues. Just like my houses' allergery issues (acculative effect), the wrist issues can be acculative too w/use. Meaning if your wrists get a workout for 'work', then you work them more in your new road riding position... well, you get the idea I think.

My mtb rides are not as long as my road rides, and positioning is all over. Which you said positioning is part of it. But the repetative working of the muscles can aid in it. I specifically stretch my hands & wrists for riding like for my pc use. Even if not pc, things like holding a pen repeatedly, etc. can do it too. I think the stretching exercises helps.

FWIW. Good Luck.