Note that in Matty Long Legs pic above, you can't see whether he's wearing a cummerbund, but neither can you see any shirt. That's because it fits properly. Search through this forum for pictures of members like Manton, Foo, Vox etc, and you will find dozens of examples of well fitting lounge suits in which no little triangle of shirt is visible.\
edit : should have said picture brillopad's pic, posted by matty long legs. Looking good btw!