Yes, you can trust it like the former Soviet Union: everything works well on the paper but once you add the people, everything gets complicated. Drawing up a size chart on paper is not a trick or anything, but as soon as realism and individual freedom of choice enter the picture, there are twists and turns. What no Size Chart published in the world tells you is the special features of the body, your own preferences, habits and feelings. It is also known from experience that few men have used a measuring tape in the pelvic area since the uncertain youth years. The material we use is very flexible and human tests have shown that an ordinary L-sized guy can wear all sizes from S to XL. S can of course feel tight and XL particularly loose, but it also stays on.