Theoretically, it should work over the long run (i.e. several months), but your day-to-day weight will probably fluctuate more. Also, I have trouble logging accurately with normal meals at home. Logging a night out is even worse. I only have a big night out once or twice a year and it pretty much guarantees a temporary weight loss setback even if I've theoretically allowed for the extra calories.

I'm going to disagree only because you give specific calorie example of 1200 more than eating goal on that day.

So at best you could have a 1000 calorie deficit, and on that day you'd wipe it out and eat 200 extra calories over - so fat storage for the extra if all the numbers were correct.

At worst you have say a reasonable 250 cal deficit, and that blowout is now almost 1000 over maintenance.
That's a lot.

There's a difference to a big day wiping out the deficit for that day, and another wiping it out and adding surplus on.
Because now you are talking about 6 days of deficit that are likely unreasonable for amount to be lost.

I'd suggest keep the deficit reasonable almost all week long, don't drop extra.
Day before drop 200 from eating goal.
Day of make a hard cardio workout to use up a bunch of glucose stores. Likely the indulgences will include extra carbs - let them go there first.
Make meals until the big meal smaller than normal.
Don't let the day go over maintenance in total - wipe out the deficit sure, but don't add surplus, and with hard cardio workout - you increased your range anyway.
Day after drop another 200 from eating goal.

That way you may have 2 days with lower than desired calories - but you broke them up with perhaps almost maintenance day.

As mentioned above, a weekly basis will get you more from the inaccuracies in logging, and the attempting to offset it by some not great choices.
Most seem to discover that doing that weekly doesn't work with long term weight loss success.