Right. I'm in agreement with KC5 as per usual. If we're attacking with Harm Reduction specifically in mind, than this is a fairly harmless situation. I understand that your tolerance is probably close to homeostatic at this point, but I think anyone who has been a truly heavy, dependent user of Opioids can express that they never truly return to zero. There is a physiological variable, in that your body has not had Opioids and is returning to a normal state, but there is a purely psychological component to what we are talking about.
Even if I had no tolerance whatsoever, I'm still not going to be able to get off on anything close to what I was using when I originally began using Opioids. So, I can only speak for myself regarding this fairly esoteric belief, but I can say that, if I were to use Opioids now, without tolerance, I would need more than a "standard dose". I have no hard evidence to cover this, but I can only imagine that introducing exogenous Opioids consistently and heavily probably causes some kind of semi-permanent or permanent change.