That’s not how it works in the “real world”
In that situation, the mechanic probably would have been fired for incompetence . . . and rightfully so, in my opinion
At some point, a professional mechanic has to use his own judgement
And if he can’t wrestle his way out of a situation where there’s no factory torque spec for a spin-on engine oil filter . . . maybe he should have a different jobs
Translation . . . it would be the mechanic’s job on the line, not the shop foreman
Torque has nothing to do with it. Here is the oil filter installation procedure for a 2010 Jeep Grand Cherokee:
Courtesy of CHRYSLER LLC
You are specifically directed to hand tighten the filter but not to overtighten.
Next oil change I’ll take note of how much I turn the filter after making contact. I kinda doubt though I’d be able to grab it up there above the frame and tighten it a full turn by hand. I do it with that cap socket but still a full turn is quite a lot. I’ve been doing it by feel for 50 years and never paid much attention to whether a full turn or 3/4 turn or what. Just what feels right to me.
Same here. It’s already wicked tight by 1/2 to 3/4 turn after contact. I go by feel and never had any issues. Keeping on cranking it down to achieve a full turn would make me very nervous about either stripping it or extraordinary effort to remove it later. I’ll take snug as the specification
Maybe following that guideline is why some come loose, they get partially stripped 
In practical terms, I get what you’re saying, and I agree. In a situation like the OP’s I’d want to be able to cite and justify a torque spec in small claims court, something quantifiable.
We have right here the perfect reason to be able to cite a number when one does exist.
As often happens when a warning light pops on but the engine continues to run the driver will continue on intending to stop at the next McDonald’s or some parts store a few blocks away or maybe a friend’s house that’s not too far and when something pops before getting there it’s got to be someone else’s fault. Oh well, C’est la vie.
10+ years back my wife drove 3-4 blocks after lower coolant hose exploded on our Subaru Outback and that beast survived the accident just fine.
my coworkers liked reminding me later how I turned pale when she showed up to our office and said “honey, I was driving next to your office and some white vapor puffed from under the hood, so I decided to get here and ask you to check on it” 
the hose and coolant was procured from Advanced Auto within the walking distance, repair took 15 minutes and she was on her way
And I hope you know how lucky you were. Can you imagine what the damage would have been if traffic had been heavy and 3 traffic lights had caught her?
Haha… I think you know that I know
Still, despite many stupid issues I used to have on my old Subies, they held up fine to both use and abuse.
Twice I’ve had cars towed in after sudden oil loss from losing an oil filter that was found to be mechanical failure and not installation error or parts failure. Luckily, in both cases the driver shut down the car immediately when the oil warning light or gauge showed an issue and in both cases the engine survived.
One was an F150 that had the oil filter come off while driving. I thought “that’s odd.” So after replacing the filter, filling the oil and verifying the engine still ran quietly, decided to do an oil pressure test. Spec was something like 50-60psi at 3000 rpm. Actual pressure was over 100psi. The oil pressure relief valve had stuck and the filter was the first thing to go. Replaced the oil pump and all was well.
The other was a Chrysler where the oil filter ballooned up and came loose. Found what appeared to be sand or something like that in the oil, perhaps put in by an ex-boyfriend. Removed the oil pan and cleaned out what I could, the engine ran when I was done but don’t know for how long.
Assuming 100% of oil goes through filter right after the oil pump, replacing pump on that second vehicle would probably increased survival chances too.
I wonder if all our stories would make @Vivian_DeMartino to get into habit of opening the hood and checking oil level regularly…
Frankly that car wasn’t really worth the money to clean out the oil pan, much less take apart the front of the engine to replace the pump. But it was the customer’s decision. Her car, her money.
Anyway, there are reasons for an oil filter to fail that have nothing to do with the installation of the part.