The Change 5 edition table on page 21 still says Area IV Task B is part of the IPC, and the preface (page 16) still says Area IV must be done with primary flight instrument inop.
https://www.faa.gov/training_testing/testing/test_standards/media/instrument_rating_pts_change5.pdf
(Note it's page 18.)
If this is what that sentence means, then the wording is inconsistent with the rest of the PTS. (In addition, it should be placed IN the task, not the preface.)
The wording to which I think you're referring:
"Area of Operation IV requires the evaluation of basic instrument flight maneuvers under both full-panel and references to backup primary flight instruments/electronic flight instrument displays."
I don't know what "backup primary flight instruments" are, emphasis on "backup PRIMARY". The rest of the PTS, when referring to what used to be called "partial panel", talks about "without the use of primary flight instruments", such as a couple paragraphs later on page 19. Or "loss of primary flight instrument indicators" as in task VII(D).
Interestingly, the same wording is used in the 2004 PTS, which is also ambiguous about partial-panel unusual attitudes.
Also, page 8, last sentence going onto page 9, when talking about glass cockpits, states: "The abnormal or emergency procedure for loss of the electronic flight instrument display appropriate to the aircraft will be evaluated in the Loss of Primary Instruments Task." The "Loss of Primary Instruments Task" can only be reasonably construed to mean task VII D, "Approach with Loss of Primary Flight Instrument Indicators", and it is telling that they use the singular word "task" when referring to when "partial panel" will be tested.
In general, I find the PTS's reasonably well written and straightforward to follow. If they intended to actually include partial-panel unusual attitudes in the test, it really should be clearer.
I'd be interested in how many people have recently taken their checkrides and had to do this.
(The argument as to whether or not these should be in the PTS or if they should be trained on is a completely separate issue.)