Because, of course, he was cheating. :-)
Not from my point of view (which occasionally was from tucked in right behind him, admiring the fine bicycle and Charlie's equally fine form, and very grateful for the draft).
The ride was great. Good conversation all the way, an effort that suited both of us, and nobody crashed. Very likely a similar piece of equipment will in my menagerie before long, and I expect I'll be delighted to use it.