That tape is junk. Your best bet is to fill the bathtub half way with water. This places much needed weight into the tub providing a nice caulk seal. I know you hate this part, but get a razor blade and cut all the old caulk out of the joint, and clean with rubbing alcohol so you will have a nice bite with the new caulk. Next, use the blue painter's tape and run two parallel lines as close as possible to the seam with one tape line on the tub and the other on the wall. Get a good quality caulking with silicone which matches the tub. Apply a liberal bead directly between the joint. Spit on your finger, which allows for a smooth joint, and make the bead feather to nothing on the taped edge. Once you get the desired look, pull your tape and leave it that way for at least 24 hours, making sure not to disturb the water in the tub or allowing water to get on the new caulking. After 24 hours, the caulk will be set and you can drain the tub and use it for years without having to redo this arduous task.
Good luck!