Just to clear things up, No Guard does affect OHKOs. However, it only works when the Pokemon with No Guard is using or being hit by a OHKO, and, since no No Guard Pokemon knows OHKOs, you'd have to use Mimic for this to help you (Mimic Sheer Cold, use Follow Me Pokemon as the rather sturdy No Guard Pokemon Sheer Colds stuff). The part about OHKOs not having a chance to "break through" it to break through Detect and Protect. Of course, OHKOs are still banned in 2v2 as far as most rules go, so use this at your own risk.
"Obi mode" could still work, but I would do it a little differently if I decided to use it.
Fast, Powerful Exploder / Selfdestructer (this is incredibly important: you have to OHKO the opponent and be faster, or they can hit the next guy, ruining everything) in slot 1...
Smeargle @ Focus Sash
- Agility
- Spore
- Endeavor
- Seismic Toss / Extremespeed / Perish Song / Explosion / not-Extremespeed priority move
And then add the usual Fake Outer. If Smeargle is hit, you fail. You also don't have the tactical advantage of being able to Endure again later. You could still use Endure + Salac to get rid of these problems, but I find the utility of multiple Endures and the ability to take multiple hits turn 1 is less than the probability that they will have a Choice Scarf Pokemon faster than a Salac Smeargle.
Alternately, you could use a Trick Roomer and a level 1 Smeargle. The goal here would be to set up Trick Room turn 1 with something like a defensive Bronzong, and maybe use Explosion with your other Pokemon. Bring out Smeargle at level 1 with as low Speed as possible that's holding a Focus Sash. If there is one Pokemon you can't OHKO with Explosion, you can hit it with Endeavor letting Bronzong's Explosion finish it off, and bring in a slow Fake Outer. There are other ways to do this, but that's just one idea.
Of course, this still has Ghost troubles, even more than End-Salac versions, because now you can die to hits or status.