I don’t know about Florida but in sunny Australia where our winter temperature today (Queensland) is forecast at 8 min to 23 max degrees Celsius (and don’t all you Poms come rushing out here as we have enough of you already) the following is my philosophy:
VFR operations ‘OFF’ except as alluded to by Formation Flyer.
IFR operations ‘ON’ at line-up and ‘OFF’ vacating the landing runway.
Pitot heat on some turbines also triggers the Angle-of-attack heater. The A/A unit will get very hot and survive about three minutes without airflow. Many thousands of $US to replace! If over-use of the heater causes damage, the hirer ultimately pays because of the increase in maintenance costs!
Foxmoth, I have never detected even the slightest compass swing caused by the Pitot Heat ON/OFF position. Can’t say the same about the windshield heater (element types) that produce a massive swing of the compass when selected to ‘ON’.