Good point about BQ.
Context is important, and almost always overlooked.
There is the racing me. I’m doing 35-40mph at the velodrome for short races. Everything makes a little difference, and it all adds up. I would say that if I’m not training 3-5 days a week, aero equipment doesn’t make too much difference.
Then there is the regular me. Not to different from the average guy in good shape. For a ride of 20-100+ miles, I’m not going to do sustained efforts over 18mph. Really, for casual, non “club” rides, most of us are going to be doing 15-18mph most of the time, not more. Just look at strava. Most of the solo rides I see are 12-16mph avg. “Club” rides are a lot faster.
And, in those conditions, gravel conditions, audax conditions, just going out for a non-competitive ride conditions, Jan’s recommendations make a lot of sense. Aero isn’t your biggest source of resistance below 20mph. Below 15mph, aero gets trivial.
And yeah, the club rides, the competitive events – Aero makes a difference.