After the advice on here, i've been calibrating before every ride. and it's pretty consistent. Sometimes I'm lazy and calibrate it without warming up, today I did it before, and then after, to compare, and the calibration number was very different - and the ride felt a lot harder (I did also get somewhat drunk the day before, so could have also been me)
I have a Kinetic Road Machine Smart 2 tire on trainer. My typical calibration number, when cold is around 1.60 - after warmup today it was 1.70
What I can't seem to find is what that number really means - I don't want to cheat the stats, ultimately I'm only cheating myself - but the control freak part of me wants to be able to blame the calibration if I have a tougher ride. So if I want to know if a higher number is harder, and if it's a linear scale, does a 5% higher calibration number mean I have to put in 5% more watts?