would you turn back with partial power?
That's a difficult question. Personally, I brief for EFATO before every T/O, but have never briefed for partial power. Would be a seat-of the-pants decision therefore, presumably as it was for the handling pilot(s). So maybe yes,maybe no for me.
That said, a turn with partial or even no power should not result in a stall/spin if flown correctly. However, Human factors training tell us that humans will make mistakes, particularly in high stress situations like an EFATO. For that reason I think most or all posters on here sympathise with the pilots concerned, despite the fact the majority view appears to be pilot error.