no, jackie, LIS is not fool proof. i've talked to lots of people, and seen posts and stories from many, who have had continued problems after LIS. thankfully, most eventually get better...but it takes a lot of trial and tribulation.
the worst mistake i made was going into my 1st LIS in 2007 thinking i'd get to move on with my life the next day. almost 3 years later and i'm still having problems. the let down and disappointment since then (and thru several other surgeries) has been almost too much to bear at times.
obviously i'm a horror story and don't mean to scare any newbies, but you just can't take anything for granted with a fissure. it's touch and go for a long time, probably a lifetime once it's chronic. find a routine that works and stick with it. don't overeat, don't drink in excess, take care of yourself, etc.....

Even though this is an older post, I thought I'd chime in. I had botox without sedation on Tuesday, although I self-medicated by taking an Ativan we had at home from the past. I of course did not drive myself down since I sedated myself to a certain extent. That helped me not be a complete basket case- that said, I had two shots, one on each side and it wasn't as bad as I expected. If I were to do it again, I would not be as scared. Not sure yet if it is helping, but it is too early to tell.
And I have to add, I am all for being put under for most anything given the choice! But that was not an option given. However, my Dr. did have to schedule mine at the day surgery center at the hospital- he explained it had to do with whether insurance would cover it- otherwise he would have just done it at the office.