Several references to a book by some fellow named Noonan. Whether he's a true authority or not I can't say, but he does appear to have several books published. There may be others but that came up quickly.
By your comment may I presume you have some authority to speak on behalf of a large contingent of lager brewers?
I have no authority. I just spend a huge chunk of my life on homebrewing forums, have done so for more than 20 years. This is the summation of my observations.
All I'm saying, honestly and realistically:
Noonan is dead (RIP), and most people don't read books anymore.
I myself could write a ton of books, but I'm too lazy and disorganized & random in my thoughts. Easier to quarterback from the armchair.
What I really mean is, brewers these days in 2024 are more exploratory and experimental. Some give credit to Brulosophy and their common conclusions that tasters could not tell the difference between X & Y, yadda yadda. And to some extent that is true. Regardless, IF there are actual rules of thumb in 2024, they differ broadly across a huge spectrum, and it depends who you ask. And so then, is it actually a "rule of thumb"? Ask 100 brewers for their opinions or their own rules of thumb about lagering, or any other topic, and although you might not get 100 different answers, you will get dozens of different ideas of what matters most vs. what doesn't matter much or at all. We're not all brewing the same way. We never will. Too many free thinkers and people trying to take shortcuts and finding out that hey, people are still buying the beer and apparently enjoying it anyway, so why overcomplicate things, or why not rush through a lager that might otherwise take 8 weeks to lager. 8 weeks!? Hardly anybody is doing that kind of stuff anymore. 20 years ago, YES, we were more rigid with things like this. Today?! Naw.
I mean no disrespect. Just being open and keeping it real in summarizing my honest impressions of how many folks brew things these days, compared to how many/most might have done a decade or two ago. Things are different. The craft is changing fast and it's not easy to keep up.
Cheers.