A general rule-of-thunb is that chemical reactions double in activity for every 10 degrees Celsius rise in temperature. Most published time-temperature charts simply reflect this, and show a straight line nomograph.(posted 8502 days ago)
What these charts don't take into account is that there is a slight difference in the reaction of the various developing agents to temperature change. Developers using only one reducing agent will behave fairly consistently over a wide range of temperature, but those with two or more, such as common M-Q and P-Q formulations won't.
What happens, in effect, is that the proportions of the developing agents shift out of balance away from the design temperature of the developer: Change the temperature, and you're effectively using a different formula.It's best to stick close to the manufacturer's recommended figure, unless maintaining that temperature is a real problem. In that case, you're on your own, and your particular use of 'Micropanatol-Z' won't give the result that the designer intended.