As Thomas recently pointed out , _Set should never be used. Instead, you should use SetXXX public methods.
Ok, but what if I need to set some properties without recording a transaction for it, in order not to trigger scrips?
This is the reading that led me to use mostly _Set in my custom scrip actions.
Shoud it be corrected?
I think we should al least add a disclaimer like “But beware that using _Set may cause strange behaviour”.
The best would be to put a list of the properties that is safe to set with _Set, and those that are not. If any!
For example, I think that Priority, InitialPriority and FinalPriority are safe, as I think they’re just a column in Tickets table. While Owner is not safe, as it’s not just a column in Tickets table 
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