Both Slipper and Alexander (and Kepu) have suffered from being mucked around between LHP and THP, or vice versa. I'll qualify my remarks by stating I was a back and there are times (OK, most of the time) the dark arts of the front row remain a mystery to me. BUT, having watched rugby for all of 48 years I hope I've gleaned at least something about scrummaging. To my eye Slipper seems to play better at THP and Alexander at LHP. And Kepu at THP, which make Dingo's decision to play him at 1 and Ben at 3 in last year's RWC look a bit silly. Like me Deans was a back, so I suppose he can be forgiven for that mistake.
The problem for the coaches when they rotate the props during a game is Robinson. I've written elsewhere he may be taking longer to recover from his latest injurty than we realise. To complicate matters Fat Cat performed extremely well when he came on last week against Argentina, a notoriously strong scrummaging nation; in fact I'd go so far as to say our dominance in the scrum in the second half was the winning of the match. But we should keep his performance in perspective: it was only for a half, the second half against a tiring Argie pack at that. Topo Rodriguez predicted his countrymen would run out of petrol at about the 60 minute mark, and he was right.
For Brisbane I'd go with Robinson at 1, Slipper at 3 and Alexander at 17. If Robinson isn't fit enough to put in 55/60 minutes it should be Alexander 1, Slipper 3 and Ryan 17. And Kepu to continue his rehabilitation in order to make the EoYT squad.