In defence of the crit (though being, as ever, on the fence), it may be true to how people actually, really and, like, speak, but it can be far more painful on the page unless it's done with great care and sparingly. It's no use saying, 'people speak like that these days,' if the readers will go away in droves cos they don't like reading it.
Writing dialogue should, imao, be a compromise thang. 
Ya, ya, Dai. Go on wit' your bad self!