The only information I know about it is from the MCAT essentials PDF on the aamc website, "Note: Each of the three scored multiple-choice sections includes some experimental items. Experimental items, as well as questions contained in the Trial Section, do not count toward your score." (AAMC, p. 6).
That's all it really says and the date on the PDF is 2013 so I assume it applies to us as well. I just know we had one question in PS that, while maybe it was sort of basic, it seemed out of scope from what the AAMC says they test on the particular subject, anyone think they know what I'm talking about?
(please reprimand me if that statement reveals too much or is a violation of our agreement)