I don't think this goes far enough.
To illustrate my point I am going to take the extreme case. Let's say you have a genial leader, with great skills in sales, manageman and business in general, a real hustler, with great taste, a world changing vision and a practical plan. This is our ideal MBA ( a rare bird). On the other hand we have a bright technical guy, with no talent for business matters. This point is important because the more rounded the technical founder, the less he sees any value in the MBA guy. In this ideal setup, even with a perfect starting position for the MBA guy, there is no rational reason for the technical guy to enter the partenership.
Because for the whole initial phase, when a product at the center of the company must be created, the technical guy is 110% of the company. Whatever the talent of the biz guy, they are yet to be proved.
Just to give an example, as far as we can tell, the RDF of Steve Jobs would not have made any difference, if he couldn't convince Woz to cofound Apple. Not just any engineer, but someone able to hack his way around hardware and software limitations. Remember Folks, Jobs had to cajole, even beg Woz to join him. And I am not even taking into consideration the fact that Woz had far more rewarding, more stable and technicallly challenging, options available right away, whenever he wanted.
My point is the biz guy, at the founding moment, must convince the tech guy of giving him 50% of his company. Any particular tactic can be used, enrolling the tech guy's girlfriend might do , but if he loses sight of his "strategical" position and its inherent disadvantages, he reduce drastically his chances to close the deal.
P.S:
Since then the situation has not gotten better for the biz guy. ( cf facebook saga)