I want to add this : Erikson himself said that you can easily read his books before you dive into the Esslemont books. I myself think that reading them in the "right" order (aka in-world chronologically) is better...BUT...the styles of the two have some differences. So it might be indeed better to just stick to Erikson and finish his series first (which is, for most of the fans that always read the books right when they came out, the order in which we have read it ... we had no choices back then ^^ ).
Btw, I know Wert is a real big-shot in the blogger-scene...but to be honest he also has very strange ideas sometimes. I guess his "fame" went a bit to his head. So don't take what he says as gospel...he's not that good.