Nobody wants to answer this question, so I'll ask it again, rephrased:
Wouldn't you rather work in a department where the midlevels (PA or NP) see their own patients, are independent, perhaps even work in a separate low acuity pod, and are employed by the hospital (not you or your group), are covered by their own medmal policy without your name on it, and without any need for a "supervising doctor" to hang their hat on medico-legally?
In that scenario you wouldn't be liable, you wouldn't have to slow down to staff patients with them, you wouldn't have to co-sign any charts, hire them/fire them or have to worry about your group affording their salary/benefits/production, etc. They'd be their own little birdie, wings a flapin' on their own. How would that be worse for you? To me, the whole extender scenario collapses under it's own weight when all of a sudden the physician is 100% responsible, yet has little if any control, and little to gain from the partnership. To those that think their group is taking in big bucks on midlevels, skimming off their production, have you looked at the numbers? Are you so sure, that after salary, med mal, benefits, funding accounts receivables and all the other expenses that you're even breaking even, once balancing out the high vs. low producers and the drag on your production to supervise?
Greg Henry wrote somewhere (I think, correct me if wrong) that there may be a day where departments are comprised of ratios of one EP to 6-8 midlevels, with huge supervision burdens to meet the needs of the system (I'll look for reference later).
That's where some very smart people think things are going, and if they get their way, do you want to be legally responsible for 6-8 midlevels and hundreds of patients per shift, or cut the cord and let them fly solo?