New 'Vinyl Flat' flattener?

I may have finally come across an LP that can't be helped. I have a copy of Mofi's Slowhand that has bad dish warping. I've kept it because side two plays flat, especially with a clamp on the record. Side one is dished up and undulated all over the place. Even if my stylus will track this I don't like to subject it to that obstacle course. A four hour run in the pouch didn't change anything(all I had time for). Maybe Mofi vinyl is different somehow. Anyway, I'm going to try an ultra long run all day while I'm at work. Really nothing to lose here and I'd like this LP if it were flat. We'll see.

I suggest trying the 150 degree oven trick for 45 - 55 minutes then let it cool. It worked well for a bad warped LP I had.

based on my experience, leaving it in the pouch an extended period, 8-10-12 hours will solve major warpage look forward to sonofjim's results....
best chump change I ever spent on vinyl.....

Well, it was about 11 hours in the pouch. To my surprise this LP is unchanged. This is in stark contrast to every other LP I've tried thus far. Obviously vinyl from different sources may vary in chemical composition. Anyone else tried this on an older Mofi? Maybe they're more refractory to intervention. It certainly is no worse than before with the same beautiful sheen. If worse comes to worse I can just keep this one for side two.
At any rate, the risk involved in experimenting with this thing seems to be quite small. I do think I'll try the oven trick suggested by Miner42 but I'll need to pick up a couple thermometers first to make sure the temperature in my oven is accurate.

I use my vinyl flat in a Breville Smartoven - a small tabletop toaster/convection oven. Works like a charm and regulates temps evenly.