Long meal- when to test?!

I'm trying to figure out when to start the 2-hour clock. And in my opinion, it's not as straightforward as "2 hours after you eat, duh!!"

Let's say I sit down at a restaurant at 12:00pm for lunch. At 12:05, the *amuse bouche* arrives. At 12:15, the light appetizer arrives (like 2-3 bites per person). Then at 12:30, the main dish arrive and it takes you 15-20 minutes to eat it. That takes us to 12:50, almost an hour of "eating".

I know the rule is to test after 2 hours of *starting* your meal, but it doesn't make sense. How do you reconcile this with the golden rule of "eating slowly"? And the heavy part of your meal doesnt start until the 2nd half of when you "sTarTEd EatInG!"

Like yesterday, my dinner salad I made at home literally took me 1 hour to eat. For this meal, I grazed on the salad ( like a cow on my sofa) for an hour. It's not like I ate half and then waited and then ate the other half a few minutes before the hour was up. I had bites every few minutes.

I'm looking for logic- I'm a logic-driven individual and the "rule" of testing 2 hours after you start eating seems too arbitrary for me.

Anyone have guidance or logic they can impart on me (before I call the nutritionist at the MFM and sound like a crazy person)?