My coworker recommended this:

https://www.amazon.com/dp/B007OXK330

I used these to fasten down the cord so it's not pulling the strip down:

https://www.amazon.com/gp/product/B072XJT436

I put two pieces on the back of the strip, and two under the desk. I let it "dry" for a few hours and then stuck the two pieces together using a rubber mallet. They've been under my desk now for a day and a half and they're rock solid. Going to start plugging stuff into them tonight.

I think you're right, and the big problem people have is that they stick them up there and immediately start plugging stuff into it. I think you should stick them up there and leave them sit for a day, preferrably clamped.

25pcs Adhesive Cable Clips Wire Clips Cable Wire Management Wire Cable Holder Clamps Cable Tie Holder for Car Office and Home https://www.amazon.com/dp/B072XJT436/ref=cm_sw_r_fm_apa_i_FCuFEbE6C02NN