Vest tops which don't cling to outer layer

[DelphiniumBlue]

Recently I read a comment on here about a particular fabric of vest that doesn't cling to the jumper/t-shirt worn over the top of it, thus flattering muffin top waistlines!
Sadly I can't find the thread or the recommendation - can anyone help?

www.marksandspencer.com/lace-neckline-full-slip-with-cool-comfort-technology/p/p22125744?prevPage=plp
This is the one I cut down, works brilliantly. And I don't think it even needs hemming!

I was just coming on to ask something similar - actually more about camisoles/vests that don't ride up. I find the cotton/lycra ones tend to do this.

Have people had success with the ones mentioned here not riding up? Or do I just need a really really long one?