I can promise you that it does go down. Won't ever go back to how it was before you took that first benzo, but it definately does go down atleast a bit. Also I wouldn't rely on any "it takes xxx days to feel the w/d" advice because especially if you are taking varying amounts irregularly, it is possible for you to be withdrawing even when still using them (irregularly). This is extremely important and it's probably what got me really physically dependant on benzos in the first place. I would have anxiety and get prescribed clonazepam 0,5mg 1-3 times a day when needed. So in the beginning I would take it a few times a day. Eventually, I would feel like the anxiety had gone away so I would take only one, or maybe even none. At this point I was already mildly addicted/dependant but did not realize it. Thus, lowering my intake resulted in withdrawal symptoms in the form of rebound anxiety, which I would mistake for the worsening of my "anxiety disorder". So I upped my dose until the "disorder" was in control again. Then at some point I probably had so little anxiety that I didn't take my meds at all for a day or two and the withdrawals began, worse than ever. It was scary as I didn't know what was causing it, I did not understand that it was the benzos (or the lack of them at that point). Then I'd take even more of them just as a desperate attempt to knock out myself and get some sleep after staying up a few nights.
Point is, you can have withdrawal symptoms if you take a drug often enough but irregularly and in different amounts, it is not necessary to completely stop taking the drug. Just like a heroin addict needs a fix of certain size for his w/d to go away, if he's used to big IV hits simply sucking on some used filters that have some heroin residue will get him sick pretty fast.
Diazepam has a long half-life that's true. But it's called half-life for a reason (approx. amount of time it takes for the body to rid half of the substance, a percentage not a fixed amount). We experience withdrawal symptoms because there's a sudden drop of drugs in our blood levels. Generally speaking taking more drugs means more drugs are metabolized in the same amount of time (atleast to a certain extent), diazepam withdrawal can definately start sooner than 17 days after cessation of drug.
EDIT: if this 2-3 weeks before withdrawals claim held any truth, wouldn't benzo addicts be able to safely take one week breaks from their meds potentially every month? Personally I wouldn't recommend anyone taking large amounts of benzos to skip their daily dose for even 3 days...
