I'd guess he left earlier than he strictly had to to make the specific appointment. The "leave now" is presumably just "if you want to be on-time", not "if you want to be on-time and do some antiquing and grab some lunch first".
I guess if you look like you're on the way, and it looks like you're going to make it on time then it shouldn't prompt.
If you do get to the restaurant around the corner and stop then it should realise that it may need to remind you.
Anyway, I've signed up for it today. I like the idea in principle, and I understand how hard it is to get this right. I assume it will get better over time as they tweak it, so it's worth giving them a fair crack of the whip.
There's absolutely no way for it to infer that 100%. How many times have people started driving to an event or the grocery store and taken a turn towards home halfway there? I'd rather be reminded at an appropriate time even if it's unnecessary than not be reminded at all.
