Originally Posted by Jellby
Once you decide that you'll do an EPUB3 book anyway and don't care about whether or not it will actually be supported... then, it's easier. But if you are not going to care about that, you could do an EPUB2 as well, and that's even easier because you just have to use Sigil
But it's easy to code stuff in Sigil that isn't EPUB2-legal. Otherwise why have the Validate function!