That's a very nice way to accelerate the rockers wearing...
You are getting me worried with comments like that!
I was always advised to bring it up to normal temps once a month to prevent the belts from drying out and cracking up, plus it spins the oil around the gearbox. Just a gentle 1st/2nd gear potter around the car park once it's warm and then back in the garage.
Should I be doing anything else or avoiding what I am doing?
Cheers, Simon.