The latest news is that a friend got me a set of Prym cro-tat hooks, so I've been re-learning how to cro-tat. I had tried it out back around 2001 or so with a hook I'd gotten from Annie's Attic, but the hook was so huge (2mm or more!) that it was just about impossible to make neat looking cro-tatted rings in size 10 thread.
My new set of Prym cro-tat hooks has three sizes of hook to choose from: 1 mm, 1.5 mm, and 2 mm. For size 10 thread I've been using the 1.5 mm hook, since that one is the closest to the 1.65 mm (size 7) hook I prefer for size 10 thread.
Here are a the hooks, and a couple of their cro-tatted snowflake byproducts:
There is definitely a knack to cro-tatting, and at the beginning it was very clear that I didn't have it. However, after practicing by making a bunch of classic tatted "flowers" (clusters of interlocking rings), then four snowflakes, I'm beginning to feel like I'm getting the hang of how to manage the thread as I'm drawing the final loop of thread through the core of all the tatted stitches on the cro-tat hook.
I'm also finding that it's working best for me to do most of the crocheting of the snowflake using my usual vintage Boye 7 hook, and only switch to the cro-tat hook to make the tatting-style rings. It feels to me that the handle on these is too far away from the business end of the hook, so if I try to do normal crochet with it, I end up grasping it somewhere around the middle, just above where the handle ends. And for full disclosure, I should confess that I always hate using any sort of steel (thread) hooks that have handles, so disliking using this one is not unexpected, and YMMV.
Another factor which I've found helpful (or not) is which thread I'm using to cro-tat. Today I tried using a ball of Red Heart crochet thread which I was not, in general, terribly in love with, but it worked amazingly well for cro-tatting. This thread is kind of... stiff? resilient?? It's the opposite of floppy. I've found that when using softer threads, splitty bits of the thread comprising the tatted stitches is more likely to get caught on the hook as I'm pulling the final loop through the cores of those tatted stitches.