New 'Vinyl Flat' flattener?

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.

I have now tried the oven at a confirmed 150 degrees and still no change in this Mofi disc from the 70's. I think I'll stop on this one after three cycle for fear of destroying the one playable side. The vinyl flat obviously can't fix everything but I've had enough success already that I'm more than sold. I think I may draw the line at two runs. If twice doesn't do it I'll stop unless I really just don't care what happens. This make 5 successes to one failure. Not too bad considering a zero success rate with other methods.