hello - welcome to the GMB

It's vastly inconclusive I appreciate, but I don't see this pattern in R. S. Williams-Thomas' book 'The Crystal Years' - unfortunately, the book includes exceptionally few examples of what must have been a substantial output in what I'm assuming is 'intaglio' work.
Technically, this method of shallow decoration differs from true cutting by being held under the wheel or stone - as opposed to cutting proper where the glass is held over the stone and the decorator looks through the glass.
Intaglio can apparently be bright polished (as appears with this piece), or left dull (matte).
Although not true rock crystal cutting, it's sometimes referred to as 'rock-crystal style in a polished bright technique', of which Thomas Webb produced examples in the early C20, and have a feeling we've discussed similar work by Jack Lloyd who was working for both Webb Corbett and Thomas Webb in the first third of the C20. Assume you've had a good look for a signature or initials on the pattern.
I suspect that as with many other forms of decoration applied to glass, this was a process that certainly wasn't confined to S. & W., and unless someone recognized the pattern you may struggle for a positive id. - lovely glass though - as a matter of interest what was the source of your S. & W. suggestion?