@russ69 Maybe 85%-90% sounds right. There are many lower efficiency, low impedance, high phase angle speakers but so many more are easy to drive (horn loaded, Tannoy's, etc.) with only one set of difficult parameters (e.g. Harbeth's-low efficiency, nominal easy impedances, my Legacys with high efficiency, lower impedances). The Apogees and MBL speakers are anomalies whereas common Maggies just need power).
Reading far more knowledgeable people on this topic, my 99.99% is much closer to the truth than 85% - 90%. I don't think it is a good idea to attempt to speak knowledgeably on a topic one is significantly deficient in. One of the forums topics I read commented that there are almost no speakers that dip below 2 ohms impedance. The Scintilla and one other as noticeable exceptions. That is only 2 out of 10's of thousands of speakers. They did not seem overly concerned with phase angle either, noting only that it would come with a loss of potential volume. I understand the math presented, though I may miss a nuance here and there.