Performance/fps drop from of_v0.8.3 on osx 10.8.5 (mountain lion) to of_v0.9.4_RC1 on 10.12 (sierra)

I recently replaced my HDD with a new one of the exact same model and went from mountain lion to sierra (big leap). I got a project I’ve been working on in of_v0.8.3 on osx 10.8.5 (mountain lion) to run on my new system with of_v0.9.4_RC1 and XCode 8.0, but somehow my setup is no longer capable of performing nearly at the speed it used to. I go down 10+fps at heavy draw times. A lot of variables at play here…

My code is pretty massive (but I hadn’t really touched it since transferring it between environments) and I have already gone thru many times in search of control flow goofs, so before I take the time to break it down and share it here it’d be helpful just to know if anyone else has experienced something similar? Is it even possible this really is beyond my code or am I crazy? Troubleshooting tips?