I guess the biggest problem is when you are not confident in your css so you use nested tables to make it look right on a desktop. These days that will never fly. Test on a tablet or phone… Uh oh. Still i guess i love the purity… Not needing css or html5 shenanigans to make it work… But then again idiots like me that use tables for layout have been the laughing stock of the design world for over a decade and a half . Html has a pretty clean elegant logic as long as you don’t use it for layout. When you start nesting elements to make it look right just stop. Dead end. If you view source… The best sites have super clean minimalist html. Shoot for that.