Thanks for the tips on environment. Yes, I am aware of battery drain in the cold and condensation issues. Condensation can be managed by avoiding rapid transitions from warm to cold and back. The trick there is to let the camera slowly acclimatise to a temperature. Battery drain can be managed with extra batteries in the pocket and/or heating packs.
I use video extensively already. Handheld from the sidelines is very good. Yes, connection to an external monitor/TV works fine, but does not provide instantaneous feedback. That's why I am exploring an on-hill solution.