Hmm... I'm not sure. He says his measurements are 33/36, but mine are 30/34 (34B, I think?) and I get almost that much compression with a sports bra. It looked fairly obvious to me when the shirt was tighter, especially with the strap on the side... seems like a thick material. Then again... I think most of my measurement may just be my ribcage, the moobs themselves are small. I'm just really obsessive, if I can push my chest any flatter with my hands I feel like it's not flat enough.
I think you'd need a review of the large size to figure out how it works for bigger sizes. It's possible they've kept that in mind and have made it wider as well as longer, to cover more.