Lots of people use different ways of keeping DPs. and have success.
As far as DP syndrome goes nothing is 100% proven, everything is kinda speculation in a way.
I like to give my Snake every possible change to live a long and healthy life and go with the advise of some proven breeders and do what works for them for generations of breeding Diamonds.
The other thing is, if you live in Sydney, there is not always a warm rock at night to cuddle up to and it can get suddenly very cold for days, just like the last few days and that?s where Diamonds live.
The Guy I bought my Diamond from, keeps his outside all year with no heating at all and has been breeding them for3 generations. (In Sydney)
He even lets them hibernate in their first year (hatchlings), just like in nature.
Others do it after second or third year.
Everybody is different.
As fare as heat goes at night, there is a book called ?Keeping Carpet Pythons?
They should be kept at lower ambient temps. Day and night (with consideration of time of year)
And if kept at too high temp. for prolonged periods will shorten their life span.