Sorry for the late follow up. I was on a bike tour with no Internet access.
I like to explain something for those bikers who are not interested in maximum speed.
My post reports the fastest speed I could obtain on a very often traveled bike route. Actually my interest is energy conservation on long tours like 100 miles (and more) per day. Average speed is just an expression of less energy needed with those tires. I have no Watts meter on my bikes. Therefore maximum average speed at a given HR (heart rate) tells me that this or that equipment is more efficient.
In simple words: There is a hell of a different feeling at the end of a 100 mile ride, on limestone, with a CF bike and efficient tires than with a full suspension bike at twice the weight and lousy tires. After the former ride I am relaxed and smiling, after the latter ride I was exhausted and tired.
This insight becomes very important on Cross Country tours.