Well I've been doing lots and lots of BTing hit 70 in 1 day and I am currently at 126 and still going.
During my team design I wanted to eliminate as much BT hax as possible, Focus Sash/Band, Evasion, and OHKOs were at the top of my list, and while I would have liked to get rid of Quick Claw and Critical Hits it would've been a bit tougher.
During my design stage Evasion was at the top of my do not want list because once a BT Poke gets enough Double Teams up they cause some huge problems and I looked at Machamp to solve that problem, but then it leaves me wide open to OHKOs. So I moved on to Lucario and Aura Sphere, the best never miss move, but then my team started looking too much like Jumpman's so I moved on again to the king of never miss, Blizzard.
But Blizzard only never misses in Hail so I needed Abomasnow, which then solves my Focus items do not want, and the team started to come together real well.
Now the team (I currently do not have the EVs due to being on a public computer):
Abomasnow Big Root (lol)
Sets up the hail, Protect lets the residual damage from Hail and Leech Seed build up and helps me scout what the AI is thinking. Blizzard is a given, strong and never misses and Wood Hammer for Waters and other things Blizzard can't really hit hard enough like Blissey. My Aboma is bulky enough to live through quite a bit, but is getting kind of slow as I see myself getting outsped quite often now because of Sassy.
Froslass Focus Sash
Hidden Power Fighting
Froslass is my anti-OHKO Pokemon, Snow Cloak + Hail essentially means that they will not be hitting me, but in the event they do Focus Sash saves me and I continue to pound away at their HP with my attacks. There have been times where I wish I had Shadow Ball but Destiny Bond saves me from things I can't 2HKO with my other moves, and HP Fighting is for the Steel/Ice types that Aboma can't really hit.
When deciding on a final Pokemon I wanted to cover up the weaknesses that 2 Ice types bring, Fire, Fighting, Steel are all easily covered by Gyara who is of the bulky variety. Taunting Pokemon like Shuckle allow me to get 3-4 Dragon Dances and usually call it game because at that point Gyara has quite a bit of HP. Leftovers keeps Gyara alive in the Hail, and while I would love to move them to Abomasnow to make it even more bulky, Gyara absolutely needs it.
The problem so far has been Pokemon with Fighting/Fire/Steel and Electric/Rock type moves as they cover my whole team really well and it requires a whole lot of thinking from me to win. I'm really enjoying the BT right now because of how much the AI trys to beat you, I've seen so many Magcargos and Magnezones over the current streak that it seems they don't want me to go much further.