If they want a 5 minute window, they need to disable the buy button after 5 minutes.
That's exactly what I said when I had to write to their support because of missing extras. I meant the 5 minute window is in itself a good idea (rather than just having the average update straight away).
I agree that the current setup is terrible, that's why I suggested disabling the buy button when the timer runs out. This would force the buyer to refresh the page, updating the average (hopefully obviously).
However, I have to say that with their contradictory definition of DRM-free, and now these bait-and-switch tactics, my appreciation of their service begins to dissolve. Plus, they didn't have so many good offers so far anyway.
They've fixed the DRM-free thing sort of... they've taken the big 'All our games are DRM-free!' sign down and they now label the games individually.
I knew something had changes and couldnt put my finger on it. Hmmm. when did this change take place?