Roy Smith wrote:

In article , wrote:
You are correct. There is no end to what some flight instructors will dream
up or invent. Everything the FAA does in the world of charting is predicated
on IAS.

The one exception would be the FAF-MAP timing chart for non-precision
approaches. That's groundspeed. Perhaps that's what got the
instructor confused.

The FAA doesn't provide timing tables in the source. The chart makers do those.
Those are still indicated airspeed. If you choose to convert those values to TAS,
then to G/S, that is your option and is a good operating practice. But, it is not
mandatory, at least not in the sense that courses and altitudes on an IAP chart
are mandatory.