this is from wowhead havoc dh guide:
" Critical Strike : As all abilities can crit, this has the potential to increase our damage by a large amount. However, with Chaos Strike and Eye Beam guaranteed to crit, the value of Crit is quite low for Havoc Demon Hunters."
looks like the one who wrote that was missinformed, i can quarantee you that chaos strike dont always crit, also crit is becoming a great stat after haste if ur playing chaos digits.