Beautiful <image> Nick, fair play to you. However, 25 minutes of stacking to produce an <image> of that superb quality is, in my interpretation, taking it into the world of AP; albeit that if it reflects what you saw on screen at that moment I can see how you might interpret that as EAA. However, by that definition surely any <image> that has not been post processed could now be defined as EAA if all it has to do is reflect what is on a computer screen at a single moment of time? I might not have put forward a suggestion that is any better than the current Forum Header definition, but there is sufficient activity in this thread to suggest that we are facing some challenges and there are some member frustrations. However, I am 100% with you that post-processing of any type should remain prohibited. But can we explore this question of what is permitted activity...?
In my location, if I get a continuous half hour break between the clouds it is a miracle, albeit that I might be able to spend four hours outside with patience and observe perhaps six objects. In three years, I have never once managed to accumulate a full 25 minutes of short stacks on any single object. What typically happens is a decent image starts to form; I might reach a dozen stacks and then my FWHM suddenly falls from 3.0 to 10 and all subsequent frames then get rejected despite my best efforts to adjust focus and histogram etc (e.g. having set my reject level to 5.0). I check outside and discover that the reason for rejections is 100% cloud and my session is over, just as it would be if I was using an eyepiece.
To me that experience is true EAA, hence reflecting what I could see in a continuous live session (albeit that I am observing 'near live' due to the stacking process). Walking away, hence leaving the camera unattended to stack indefinitely and observing only every five minutes (just as you did) is, in my humble opinion, into the realm of AP and posting images of such quality that don't reflect a continuous live observing session and instead only a single moment in time raises the expectancy of noobs that simply want to beat light pollution, yet end up being lured into buying unnecessary expensive AP equipment because they think they should be able to replicate this. That is how I spent so much money and now have boxes of redundant kit.
My 'images' of the Orion Nebula are great, but if I posted what is possible from typically fewer stacks from my almost perpetually cloudy location as regards any harder targets then the 'Imagers' would rip them apart with criticism. But EAA is allowing me to see DSO objects (like the Horsehead) that are utterly impossible using an eyepiece from my light polluted back yard. But to me, this is the very definition of EAA (e.g); it is the limit of what I tangibly saw in a continuous LIVE observing session. No post processing; no walking away to permit sufficient stacks and only checking periodically; and any breaks in observing for merely for reasonable comfort breaks.
In summary, I think we should perhaps be seeking to find a definition that embraces the phrase "..continuous live observing (NV and stacking permitted)..."; whilst prohibiting any form of post-processing. Walking away and observing only every five minutes largely to check how an <image> is progressing is not EAA. But if I ever do get a continuous two hour break in the clouds I will definitely attempt it, but would report my results in the astrophotography forum.