Well I've solved my own problem. Turns out the secret was spending countless days troubleshooting every possible fix, then give up and post to the forum.
Right after I made the above post I tried two more things. One, I updated some windows stuff, including net framework stuff. At the same time, I also decided to dig into the scripting Hooks directory. I figured most mods were already removed by renaming the Mods dir and eliminating all the references in export.lua. I was wrong. Renaming the hooks directory fixed the problem completely.
I drilled down a little further to figure out which file exactly was causing the problem. Turns out it was the gunner export .dll and .lua that the otherwise excellent OH-6 mod added. With them re-added the problem was back, with them gone everything is fine.
I like that mod, so I grabbed the newest version, which just released a few days ago. They must have updated the .dll or the .lua, because with them back in hooks I'm still stutter free. Well, as stutter free as anyone is in DCS.
Hope this helps someone else out there.
Also, it should would be helpful if DCS had a safemode with options to boot with an alternate (and empty) Saved Games\DCS directory.
