I didn't think it was a dangerous technique, considering how slow I made the cut. However, after reading all the comments, I think I'll avoid it in the future and simply order an inertia bullet puller.
In the right hands, with the right mind behind them, alternative tools can be useful and effective. I don't see anything wrong with calculated resourcefulness. I too cringe when I see SOME people use certain tools for certain things, but I also marvel at the ingenuity of it - in the right hands.
I HATE inertia pullers. They're like any other tool designed to do a particularly unsavory task, like a toilet plunger. Worse, they make a lot of racket and disrupt the quiet calm of my shop and my reloading pursuits. I broke my first one, which I had to buy to tear down 50 rounds of 44 Special I loaded when I got my first Bulldog. There was a lot of feistier 44 Special data much more readily available then, and I used a significant bit of it. The offending loads had not caused that stout little dog any consternation at all, but they were actually unpleasant to shoot. By the time I'd disassembled 50 of those puppies, I had to wonder which way was worse. Whacking my wrist and assaulting my ears ('muffs in either case) with the Bulldog - or the inertial puller?
THAT was the last time I loaded that many of ANYTHING for the first go. Of course, I lived in an apartment then, and the range was a bit of a drive, plus several calendar days away, meaning I had to wait for the weekend. That made testing one or two sort of a pain in the butt. We all end up balancing which pain we'd prefer to feel when put into a corner, and that has an affect on how resourceful we decide we can afford to be. Given the experience-level in question, I think a logical conclusion, following reasonable logic ensued. Given the level of experience.
Like I said, I broke my first inertia puller. When it shattered, I swore off them. Eventually, I had a small deposit of questionable cartridges leering at me every time I used my bench. I begrudgingly bought a new one, and in the past thirty years, have HAD to use it a small number of times. It's looking haggard though, even as I use it very infrequently. Sitting on the top shelf and not in use, it is a silent and painless threat of the dreaded racket and pain it can inflict and makes me very apprehensive and very careful, yet there are those times, just as for anyone else. When I DO use it, I beat that sucker like it did something to one of my kids. It's sad, really. It's saved my butt a number of times, yet I treat it so savagely. I do respect that tool, that insidious implement, but it probably wouldn't know it by how I treat it when we have to interact physically.