People are talking about three different things throughout this thread.
1) The scope itself should not have a loss of mechanical adjustment provided in the course of normal removal of the mount from the rifle, and the scope from the mount and rings. If you had it adjusted 35 clicks left from the mechanical right stop of travel, it should not shift from that position. Now if you for instance (worst case) install the scope 90 degrees of rotation off, those 35 clicks don't help much in having PoA/PoI be the same. Getting all three pieces (the scope, rings, and mount) back onto the rifle without having a PoA/PoI shift is in general not going to happen. You will probably want to do a rezero of the weapon.
2) If you remove the scope from the rings, and re-install it in the rings again without removing the mount from the rifle it will be very difficult with most systems to not have PoA/PoI shift. The minute positioning of the scope in the rings, torque variances, etc, will normally cause a PoA/PoI shift that again may necessitate a rezero.
3) Leaving the scope secured in the rings, and assuming the mount had been properly mounted hard forward against the recoil lugs, and removing the mount has a decent chance of having minimal PoA/PoI shift. Most mount interfaces (weaver, picatinny rails, etc) are manufactured in such as way that so long as mounting surfaces end up in roughly the same place with roughly the same torque you will have a repeatable mount. A good QD picatinny mount can see no discernable change in zero when remounting.
-Jenrick
