Can o' worms!
Actually Chris, when if comes to a single media, I think that you CAN deal with specifying pretty tightly what YOU want to handle as what YOU will call "handmade". Since YOU are the boss in the matter, you call the shots. You simply list exactly what processes are acceptable for the show/fair/venue.
Ceramic work submitted for this show/fair/venue must be produced as follows:
By a single artist who handles all of the steps of the process from forming to decorating to glazing to firing.
Exclusively by the methods of coiling, pinching, slab building, wheel throwing, handwork plastic clay press molding, or hand carving.
(Forming methods specifically excluded include slip casting, pressure slip casting, jiggering, jollying, hydraulic pressing and 3-D computer printing methods.)
And so on.
Yes... the jurors/organizers will sometimes have some issue identifying if pieces are actually compliant.... but that is the reason they are getting paid to do the job. And sometimes they WILL get it wrong. Such is life.
If this kind of stuff is presented totally up-front, then the public and other artists know exactly what to expect. And yes... this kind of specificity WILL potential exclude some people who might sit on the "edges", production-wise....... that "is what it is". Sorry. As they say.... 'my football.... my rules'. Some consumers will care....... some won't.
My "issues" with all this "what is handmade" stuff revolve around what I term "Truth in advertising".
I don't care how a well designed object is made as long as I am not being mislead as to the genesis of that object in one way or another. If people openly specify how work is made.... I can decide for myself if I consider that what I personally define as a "handmade" piece, and if I think that FOR ME the pricing is appropriate to that work.
The problems come when the venue does not require that information. And/or when the producer of the objects is concealing or lying about the nature of the work.
A great example of this is one very well known ceramic artist with US national acclaim. A large portion of their heavy production work is jiggered/jolllyed. It is regularly sold in "handcraft galleries" along side hand thrown and other such works. The hang tags and the info on the pieces does not indicate that forming methods for those pieces. The price points are not typically lower than other hand thrown work. For a long time I made a point of going into the shops that handled their work and asked the salespeople about the particular pieces. 100% of the time I got told how the pieces were hand thrown on the potters wheel! I then took the time to explain to the salesperson how that work actually was made. They usually were quite surprised. But if I went back later... the work was still there and still making people THINK they knew how it was made.
The pieces in question there are beautiful. But from MY definition (and I bet many other people's) they are not "handmade". They are "limited manufacturing" or something like that. SO for me,...... I would not be paying truly "handcrafted" pricing for them. And I would not tell anyone they are "thrown". I would say that they are great serving pieces....like much of the work from places like Noritake.
When what are euphemistically termed "assisted technologies" in the ceramics field are used specifically to increase production rates and/or reduce price points...... and the work is then offered for sale in venues that the consumer would expect a high involvement of "the skilled hand" to be involved........ then I think the work has moved outside the realm of "handcrafted". For ME.
For example "slip casting" or "hydraulic pressing" can be used for many end-goal reasons. One or them is to allow the forms to then be manipulated in such ways that it is the best ways to create certain end forms. Things getting cut up and reassembed.... multiples arranged in arrays or installations....and so on. The other end of the spectrum is to use those forming methods to produce multiples at a high rate with less skilled handwork either as a goal to increase production or lower price points to increase market share. For ME....... the first is "handmade".... the second is "assisted technology".