first of all we should probably clarify that traditional and slipjoint are two terms that shouldn't really be conflated , not all slipjoints are automatically traditional and many traditional knives aren't slipjoints.
To me there are conventional traditional knives.
Those that are slightly modernized.
Then you have modern / contemporary slipjoints and modern two handed lockbacks.
The latter two can be gray areas, or just sometimes disputed by people who just want to be thorny.
The less conventional more modern stuff can be a gray area , it just depends on how close it is to a conventional traditional knife and whether or not the maker wanted to blur lines or something.
If you change too many little details here and there you can end up with a Barlow inspired modern knife instead of a Barlow with some modern conventions.
That's where the line is when you've already eliminated the disqualifiers like pocket clips and thumb studs.
Is it just a conventional true to pattern slipjoint that's screwed together and maybe has some modern materials, or are the blades unconventionally shaped and are there any overly modern aesthetic elements.
It's like that old saying " if you have to ask you already know the answer ", except when it comes to swiss army knives which people frequently have to ask about for some reason the saying mostly holds true around here.
The last one is really not a gray area to anybody who really gets the program around here ( the typical / general atmosphere is old timey knives) , but some people just want to think any slipjoint should automatically be considered traditional and belong here on the porch.
People have thrown fits over Benchmade and spyderco slipjoints because they wouldn't accept that they were not traditional knives. It always seems odd to me when somebody gets upset over not getting to join in here when they don't seem to actually have any interest in the types of knives we discuss here.
I personally like my traditional knives to be entirely conventional.
The modern materials and construction methods just don't interest me, but as such I exercise my ability to only pay attention to the stuff that does interest me.
