Why would you want to fly in a SEP plane in conditions that require de-icing anyway? Just don't go. By far the safest solution.
Because when it's gin clear and CAVOK but has got down to -10 the night before there is no reason not to fly...it just takes a very long time to get several mms of ice off the wings when one has quite a large aircraft or lets say rain from the previous night has frozen solid on the wings and is very difficult to get off.
The best way to De-ice is to put the aircraft in a warm hangar.
Yes I am of course aware of this... as I stated in my post the aircraft usually lives in a hangar at my home airport. But as you no doubt know that is not always a possibility or is at prohibitively high cost.