I had another look at it after the question...and it is nothing like my other crackle glass pieces. I think you would be hard pushed to create that level of crackle by dipping and reblowing without it falling apart...but again I could be wrong. All my other crackle bits are fairly 'un-uniform' in their crackle, i.e. there are 'patches' of smooth glass between the crackles and some are tiny and some are large. This piece is uniform in it's texture, quite sharp but not cutting sharp as it has been melted slightly. I am pretty sure it is overshot. It's just that Matthey Crinkles for example are much smaller bits than the shards used on my glass, and with Matthey pieces, once the glass has been rolled in Matthey crinkles it isn't blown out any further, leaving a piece just covered in the 'sharp'teeny tiny bits of crinkles, which makes it feel like sandpaper.
It's all the overshot technique, but the final outcome depends on how big the pieces of overshot were and whether it's been blown further or not I think.