Consider this just me doing research on the issue, not trying to argue with you 
I created a spreadsheet in Google sheets. It factors the following:
Day, time of day, actual solar panel production, the load of charging my EV on a 16A circuit with a 30Kw battery, the net solar gain (minus the EV charge), the amount of grid power needed additionally for the charge based on the time of day, the time of use rate per hour, my solar credit value, and the net cost.
This is all based on actual figures from my electric bill and an automatically generated chart of solar production.
Just for two days in June.
Not sure how accurate it all is, but it's a start. I'll keep working on it.
EDIT - the following is wrong, read later post for clarification...
Conclusion so far: there is a 'best' time to charge the EV- it's at night.
I make 8c per kw selling my solar but if I charge at night I pay less than 3c/kwh. A simulation suggests that I'm consistently better off charging at night.
So you are correct that there is no advantage to charging during the day.
But your statement that it doesnt matter when the consumption occurs is not right - it's definitely advantageous for me to charge my EV at night.
I may well still build this project for testing reasons and because there are plenty of people - those who don't have net metering - who may well find a solar controlled charging switch to be of value. But myself, I won't be using it!
Solar EV charging costs - Document1.pdf (35.9 KB)