Its a tired response. I had all inpatient with residents for my cores. I rotated alongside MDs for a number of rotations as well. I had maybe one rotation in 4 yrs that I would call mostly shadowing. Had people in my own city tell me that the problem with DO schools is that I don't do cores with residents as a DO and do mostly shadowing. I lightly corrected them and moved on.
I'm aware of people that went out of their way to do outpatient only or small clinical site rotations with no residents. You shouldn't be able to do that, but inconsistency is still a big issue at DO schools and I agree we should fight it and strive for better. That said, in all seriousness tons of MDs have the same complaints and I met more that did less wards team-based rotations than I did and actually did more shadowing. They had more consistency across their class though.
Outpatient surgery for a core certainly is a joke, but again my surgery cores were 1.5 blocks of Gen Surg with surgery residents (scrubbed into a number of choles, appys, hernia repairs, and a few colon resections) followed by half a block of Ortho (with a rotating ortho resident) and still got to scrub into BKAs, SCFEs, knee replacements, and random pinning (mainly lower extremity stuff though). Again though, it was variable because I went to a medium sized hospital and I know some students that barely scrubbed because of low volume when they did their rotations.