One thing that has been mentioned is the potential of an Armageddon-type scenario for Sky (less so Froome IMO), that being Froome getting a ban. Given their well publicised stance on drugs and bans, they would be obliged to sack him. If they didn't their credibility would be as good as zero, and if they did then who would take his place, not to mention the bidding war from the other teams, as I believe that is what would happen, hence why I caveated Froome out of the potential situation because I think he has that kind of focus to not worry overly much, case in point being his noticeably delayed statement on Brailsford and the Jiffy bag palaver.
From what I've read, Sky are going to go down the road of dehydration (apparently 2% can impart this level of reading), and/or various physiological quirks with which to explain away the result, which is fair enough as they want to protect their prize asset, but at the same time seems a bit "wriggly" IMO.