Hi James.
Does the technique you are describing result in elongated bubbles trapped in the glass? These are definitely long bubbles. If I run my hand around the inside of the mouth, I can feel raised ridges of glass that define the bubbles in the body, not as much on the exterior, but they are there also. Although much less pronounced, I can also feel raised areas on the exterior of the lower portion of the body of the vase which correspond to the larger trapped air in that region also. Where the body thins down the furthest and the bubbles are the smallest, the ribs can not be felt on the inside or the outside of the vessel. If I look at the vase with a loupe, I can see the interior surfaces of the bubbles.
Thanks, Craig