A few points about Taphsic (that's what your referring to, right?)
1. I have never actually done one, so you can disregard the rest of what I say.
2. The handbook recommends keeping the term of the Taphsic short, at leat at first, and renew it when it expires. The example given is a week at a time for "beginners."
3. עיין שם in Masechtos Nedarim and Shevuos. A "Neder" is an issur cheftza, like "
this loaf of bread will be assur to me like a korban if I......" Whereas a Shevua is an issur Gavra that you create on yourself, as in "I take a shevua that I will...."
The taphsic (as presented in the handbook) is a shevua, not a neder.
4. The way that is recommended to form the shevua is to not directly punish the acting out, but to provide yourself with an incentive to distract yourself. For example, "If I act out, but I: went for a jog first/learned first/said tehillim first/whatever other distraction you can come up with for a set amount of time, then I will have to do a small k'nas. But if I act out without using any of my distractions first, then I will have to do the big k'nas."
5. As far as whether it works, like I said, I never tried it. Those who have say (I think) that it is only a tool but it is not THE Solution.
Hope that helps.