As someone pointed out in another thread, there are some PDs who don't consider DOs...at least in Dermatology. I'm not defending that, but it's the truth of how things work currently.
I'm not at all trying to add fuel to the fire, but it has to be considered that people have different definitions of what a great doctor is. To some, a great doctor is someone who is good with patients, rocks diagnoses, gets the job done, get people better.
My personal opinion of the best doctor is someone who can rock diagnoses, is good with patients, gets people better, and does meaningful research and academic work to advance the field of medicine.
There are DOs and DO programs that do research and I'm sure it is encouraged in a lot of places. But it's hard to disagree with the fact that way fewer DO schools are pulling in the NIH funding that allo schools are.
If someone's definition of a great doctor equates with a great clinician, then I think the chance of a DO and an MD both being about equal isn't far fetched at all.
However under MY opinion (and I stress my because it is my opinion, I don't care if other people share that opinion, nor should others care if I don't share theirs), allo track people in general encounter opportunities that give them the chance to integrate research into their careers, especially at top training centers that are pulling down the research cash. This translates into what I (not only is that I capital for grammatical purposes, but also for emphasis again) think makes a doctor the best they can be. That doesn't mean those people automatically utilize what is offered to them to the fullest. and...sure, DOs get into top programs and do these same great things. But in general, it's just more likely to happen for an allo grad in the current state of things to be given those opportunities with which to work.
In the derm world, since that is with which I'm most familiar, research...past, present, and future, are pretty highly prized. Although DO's do research, I'm guessing some PDs may not see it as equal. That may be some of the reason why some PDs don't give DOs as much consideration (or any consideration by some, unfortunately).
Again, I have my opinion what makes the best doctor. I think being a doctor is better than being a financial advisor. I think Fall is better than Spring. I think blue is better than red. Whatever. My opinions on these matters really shouldn't matter too much to others...in my opinion.