As we talk about whether three face-to-face meetings per year is the magic number, I suggest that we keep a few things in mind, because the definition of "face-to-face meeting" isn't constant.
I am very gratified to see the number of hackathon participants at each Hackathon, and the number of hackathon participants who stay for IETF meetings, even after the hackathon is completed. The hackathons are still fairly new - the first was in Dallas, at IETF 92, and they've grown over time. Those are easier to do, face-to-face.
I am very gratified to see the number of side meetings announced at HotRFC and held during the week, especially when (as in Montreal this week) it was easy to schedule them during open time each day during the week.. Those are easier to do, face-to-face.
The IETF 105 Deep Dive on NICs wasn't as strongly cross-area as the IETF 104 Deep Dive on spherical routers, but it was still cross-area (as well as useful). I have already had conversations about possible topics for future IETFs. Those are easier to do, face-to-face.
I have no insight as to why there were only two Sunday tutorials, but that's lower than usual (four Sunday tutorials is probably usual). Understanding whether that's a trend would be useful.
For your working group(s) - the decision about how often to meet is almost entirely up to you. Working groups like QUIC have scheduled additional multi-day meetings including interop testing three times per year (although if the working group needs change, that pattern will change), while other groups routinely skip IETF face-to-face meetings, have virtual interims, and may schedule other ways of moving work forward as their needs dictate. TL;DR, if you think things should be different for your working group, you don't have to get the rest of the IETF to agree to change your behavior.
But Do The RIght Thing(s), of course.
Spencer
