Douglas - I would be interested to know what your bloods did over the 24 hours since your amazing result yesterday morning.
I conducted a similar experiment, just before Christmas, with pizza. I knew it was "left field", Whilst my postprandial reading was under 6 a couple of hours later, my waking and subsequent numbers were just a a little raised, on my usual averages, for a couple of days thereafter. By a little raised, I mean 0.5-0.75 mmol/L. As I was experimenting, I deliberately stuck with food I can predict my results, and not moderated on exercise - before and after the indulgence.
I appreciate I am trying to run my numbers very tightly, but whilst I'm still trimming up and getting the old cholesterol and BP reined, it seems eminently sensible. The experiment was only two months post-diagnosis, so I may try something similar again soon.
I must say, your experiment is encouraging, for the odd indulgence on high days and holidays.