I like putting the red everywhere, plus smilies stick out of them and it's disproportionately amusing
You can, but you need to copy and paste it somewhere else. It's incredibly clunky and stupid for a code that literally offers no advantages over well-used spoilers other than the lulzy emoticon peekaboo.
it's even better when you copypaste it into a document and it persists as red-coloured red-highlighted text that you still cannot read