In ST using something like Core or even SmartLighting (and if they support recognition of double and triple taps) you can set it to open to a specific percentage or a fully open or fully closed position. If you are looking to have the shades stop when you double tap, you might have to make a custom DH to send the stop command. It really comes down to what ST itself will let you do since all the shades really do is listen and respond to the commands being sent.
Hope that helps! Also feel free to PM me any time.