It's an unsubstantiated attack because you're not giving us any evidence other than your Craigslist-quality rant. Does Cambridge send all these resources to every call? Where are you getting all this from?
The primary redeeming quality of P/B staffing is that it's cheaper. That's not a minor benefit; 911 service is expensive, and with transport times from Cambridge, ALS interventions aren't crucial. Less expensive ambulance staffing that provides appropriate care benefits patients, taxpayers, and Pro employees.
What a strange argument. You start with an ad hominem (No True Scotsman flavor), move on into judging the worth of an EMS system setup by response times, admit you have little to no evidence, use terms like "optimal" and "critical" that allow you to move the goalposts, and ignore the whole concept of cost-effectiveness. Your hospital analogy is also ludicrous, unless you plan to argue that dual-paramedic ambulances provide care equal to that of a hospital rapid response team (in some hospitals, you might have a point).
This all leaves me wondering why you're so filled with vitriol when discussing Pro, especially when it's tangential to the thread.