Playing HU. openfold on the button pf or not?

In HOH, Harrington says that you should always call on the button when playing HU. This is because you have position and because of the 3 to 1 pot odds.

I watched some CardRunners videos and in that you see them folding a lot pf on the button. Also, if you watch the high stakes games on FullTilt you also see players folding on the button. In the CardRunners videos they even mention that never folding on the button is a big flaw in many players games - and you know that you are playing a weaker when the call/raise every single time on the button, but never fold.

When do these 2 pieces of advice apply. Are they referring to different situations? (ie. cash games/tourneys. deep/short)

Personally, when I'm playing heads-up with deep stacks I'm raising my button like half the time. I don't bother to limp with my worst hands because my opponent would know that I have complete junk since I didn't raise. So I just fold them.

The section of HOH on heads-up play is pretty bad IMO, but in Harrington's defense, it just takes too much poker experience to get good at heads-up play and you can't expect a book for beginners to teach you to be good at it.

BTW cash games vs. tourneys is irrelevant in heads-up play, only stack sizes matter.