Sandy, I had missed your earlier post.
Just to add, John has PPA, which is a variant of FTD. He was prescribed Reminyl because he was wrongly diagnosed as AD initially -- and it worked for him!
As for coming off medication, I think what you say is correct, and there may be a dramatic downturn if a person is taken off it early. However, if it is continued to end-stage, when it has ceased to have an effect, there will not be a downturn (at least there wasn't in John's case.
That's why it's normal to take someone off gradually, with the proviso that treatment will be reinstated if there is a downturn, as this would show that the drug was still working.
And another reason why NICE guidelines are wrong. A score of 10 is much too early.