Ok, I cooled down and got around to emailing him a response which was:
Hi H,
Happy Easter to you too. Glad you enjoyed your dinner and your run.
It's cold here too today. Yesterday was marvelous though, and I did some photography. It was really good.
Say hi to everyone there. My parents say hi as well.
Enjoy your trip back.
I'm really not convinced this is working all that much to be honest. He just keeps emailing every day, and that's it. Ok, well, I will see him tomorrow when he drops the car back off. Any advice prior to that would be most welcome. Thanks!