I don't care whether it is your favorite recipe or someone else's mad scientist concoction, when you go outside of tested and published loads, you are in uncharted territory and you do not know what pressures you are playing with. And yet, reloaders brag about doing it and "getting no pressure signs". They don't know. Hot loads means anything above published max loads. And the fact that different loading manuals vary widely just makes it murkier.
I remember about 20 years back when piezo pressure transducers became the norm, there was a technical writer who went back into old reloading data published by PO Ackley and Speer that tested 15-20,000 psi higher than SAAMI max pressure specs. I have had people bring rifles to my shop that were totally locked shut due to their "hunting loads". We had a man bring in a 722 in 300 Savage that he had loaded to 308 max loads. The rifle was essentially welded shut, but he was mad at me for turning it away and he swore those loads were just fine because "300 Savage is the same as 308" because the 308 was developed from the 300 Savage. I can't count the number of bolt handles I have brazed back onto Remington 700s and 721s because the rifle "had to be beat open", and yet the owners swore the loads were safe.
So, long drawn-out way to say it, but you don't know what pressure your loads are developing. At best you guess based on "pressure signs" and measuring case head expansion or gauging bolt lift or estimating due to primer pocket expansion. Those things don't tell you much at all because you don't know the hardness of the brass, or its flow characteristics, or virtually anything except traditions taught to you by a mentor (real life or publication). Don't get me wrong, I've done it too. But anything beyond published loads in a factory firearm is venturing into uncharted territory and your loads are "hot" and therefore suspect.