Hi Under,
The other thread about 'positive reinforcement' isn't so much a reaction as pointing out something that seems to have been forgotten or just gets little attention. If there are two sides to everything, in this case helping someone to see the truth about the truth, then you have the matter of hacking away at the falsehood and the 'positive reinforcement,' or again really just pointing out what would be a readily evident truth. Only using the sword to hack away can leave people feeling disintegrated, but when you encourage them to look at what they in effect already know then you are kind of empowering them in a way.
Even the doing away of false beliefs doesn't have to take a particularly violent form, although often it just works out that way and can be appropriate at times. Just asking a question in an open way can really help, but there is this tendency to want to draw the conclusion or lead the person to it. It's funny when I was studying the Live Forever book I remember them getting kind of frustrated that I wasn't giving the right answers to the question, and then they just end up telling me the answer. But what I'm saying is if you ask the question in such a way as to arouse the person's own curiosity then they can find out for themselves, if nothing else the beliefs will truly be called into question rather than just negated by some opposite thought you present to them. The advantage to this is even without drawing a new conclusion the power behind the belief is already gone if it is called into question. The positive reinforcement would really just be a slight nudge for someone who is curious and wants to find out for themselves, and in that process of looking for what's true they will naturally retain a certain integrity rather than feeling like they've fallen apart.
You might look at it like the difference between doing all the negative, destroying false beliefs first and then trying to build up something functional, and doing both a little at a time, cycling between the two sides until the process is complete. Frankly it's because you got this thing called a person, and most people are not so gung-ho about the truth (the real one) but need a certain measure of stability in their mental makeup. If they were so on fire about finding the truth they probably would have questioned The Truth and be out there searching without anyone saying anything, but often it just doesn't work that way.