I haven't heard of "DIF", but in my experience, a lot of legginess comes from CO2 exposure and is a little less reliant on (overall) moderate temperature swings, at least in Veg. Obviously temps are super important, and there's big reasons why outdoor grows prosper at a particular time of year, and that variance would be seemingly fairly common in nature.
That all being said, I'm going to go look into DIF now and glean some additional info so thanks for letting me know about it!
This is the best article I found on DIF. ( I also watched a video by a commercial tomato grower who
hired a horticulturist to explain why he was getting longer node spacing, randomly, on his tomato plants.
The horticulturist explained that the longer spacing happened when he had had cooler early spring nights in the greenhouse. )
