Not so, DN. On a low vis approach (decision height<200') all heights, call outs and minima are referenced to rad alt.
Very interesting, Darvan/Peacock, although in the context of this thread I stand by my "red herring" comment since such a unique self-generated alt setting is neither QFE nor QNH.
I'm intrigued that formation aerobatics has been thrown in as a reason for QFE. Although USAF's Thunderbirds use QNH, they had adopted the practice of giving their height checks and "gates" for various manoeuvres as heights agl rather than altitudes. This practice led to the spectacular (luckily non-fatal) crash described by easy st. and ceased thereafter. But great video on youtube!