I think what he means is that the way Poyet departed and Garcia appointed late that summer meant we lost momentum and have been stuttering ever since.
We sneaked into the play-offs in an easy division last year knowing we were nowhere near the quality of the top 3 and now we are struggling to get going.
While Gus was here we were moving forward nicely and the acrimonious split put paid to that.
I would probably agree with all that, though I think it's daft blame Poyet ENTIRELY for the acrimonious split and not anyone at the club at all, when we simply do not know what happened between Jan-March to make Poyet suddenly fall massively out of love with a job that was perfectly set up for him previously.