Founder's Co-op likes 2 (and 3) person teams

We have 2 portfolio companies at this time and we've seen success with 2 person founding teams. I've also had a lot of personal success with 3 person founding teams. I recall there was a study done at MIT years ago that looked at the number of founders and success of startups as measured by revenue 1 and 2 years after founding. It turns out that the success of your start up is directly correlated to the number of founders up to 4 and then it starts to decrease. The theory behind the article makes intuitive sense -- up to 4 people working together can make more traction than just 1 sole entrepreneur.
In addition to the research above, at Founder's Co-op we're seeing these 2 person teams work very efficiently and effectively. The teams both have 1 business and 1 technical founder.  The companies are able to make substantial progress on both product and business each day because of the diversity of skill.
They're both ramping revenues in the first 6 months of operations and I'm super bullish about both companies. If you're applying to Founder's Co-op, you should know that our default preference in terms of number of founders is as follows:

  1. 2 founders: 1 technical and 1 business
  2. 3 founders: 2 technical and 1 business
  3. 4 founders: 2 technical and 2 business
  4. 1 founder: 1 technical

I tell you this because this is our preference -- this is not a rule. I'm sure we'll fund the single business guy too one day. That said, I highly doubt we'll fund a founding team of 5 or more -- just too many founders and too much founder conflict. By the way, my first company, Firefly, had 7 founders.