So instead of settling the matter early using something like a vesting schedule and then moving on, you're supposed to continually argue about what coefficients to assign to your contributions in some equity formula?
And in other news, those that can, do; those that can't, teach.
But I think it may be a step in the right direction. Simply stating that the business's equity is dynamic might be enough to allow more communication, which might help to dispel or at least lessen hard feelings and grudges.