IIRC when vinegar dosing (any organic carbon dosing I think) usually the nitrate gets eaten up relatively faster so that you end up with near zero nitrate but enough phosphate lingering to still cause algae issues unless GFO is used to deal with the phosphate. Something about that redfield ratio thing, although it doesn't perfectly or accurately carry over to our purposes, it seems that we usually import a ratio of phosphate to nitrate that is different from the ratio that is taken up by bacterial growth, hence the accumulating phosphate.
IME modest vinegar dosing works well overall, but without any significant GFO usage my system has been very good at growing valonia and cyano, but other nusiance algaes seem to be minimal or absent. That said, I've been far from meticulous about my tank for the past several years so I'm sure I could have things dialed in a lot better if I was more invested in keeping up with it.