online pros have a edge over live pros imo.
example: tom dwan over PH in cash games. lol
Hardly a fair comparison - pretty much all pros both live and online have an edge on Hellmuth in cash games. You could just as easily substitute Negreanu, Greenstein, Kenny Tran or any number of others for Dwan in that sentence.
Now - FWIW I think yes, the edge live pros have over the average players in their games is bigger than the edge online pros have over the average players in their games. That's a combination of a bunch of things though.
For one, the average player in a live game (even the stakes pros play at) is a lot worse than the average player in an online game.
Second, I think the people who say tells are overrated are overrating the idea that tells are overrated. It makes about as much sense as a live player saying HUDs are overrated online. If you know how to read physical tells (and one of the most important parts of being a live pro is being able to do that) you've got a big edge over your opponents who don't know how to.
EDIT: one other thing. This is all largely a moot point anyway because like a lot of other things, it's $/hr and not the size of your edge that matters.
Who cares if you can have a 15% edge on your opponents live and only a 5% edge online. The game you should be playing is the one where you make the most $/hr, not the one where you have a larger theoretical edge.