I only know what Martin's warranty will cover, as I have a luthier buddy who is the local Martin Warranty Center. They will cover the work to the dovetail, only. No fretwork, no planing of the fingerboard, no nut and saddle work.
If the neck reset is done properly, the scale length doesn't change. THe dovetail is only cut or reshaped near the neck heel and tapered towards the fretboard. In essence, the point at which the neck joins the body (12th or 14th fret) is the pivot point. Being the pivot point, it does not move, the dovetail is cut/reshaped to allow the neck angle to change without moving the 12th or 14th fret position relative to the body. If you look at a guitar before and after a good neck reset, the body/neck join will always be exactly as it was before. No need to move the bridge, but almost guaranteed to require a new saddle due to the new string height/angle.
Shaving bridges only buys you some time, a neck reset will still be required.
Regarding the "hump" it may or may not occur, and it may or may not be important. The "hump" really depends on how much the neck is moved in terms of angle, and we are NOT talking about 5-10 degree movements here. Usually it is less than 5 degrees, and the few degrees of movement may raise the tail end of the fingerboard, but the fingerboard may also either be glued down, or a wedge may be placed between the bottom of the fingerboard and the top of the soundboard. Whether this is acceptable to the player is between him and his luthier, but a wedge can actually lead to a better action in the last 5 frets than trying to glue down the fingerboard end, and replaning the fingerboard. Other thing to keep in mind is that the neck is being restored to it original, or very close to original angle, and the fretboard end was correct when the guitar was made. Resetting the neck tries to restore the propler angle, and this also applies to the fingerboard end. If it is an exceptionally stiff fingerboard, the above mentioned wedge may be used, or in a less stiff fingerboard, the fingerboard can be glued down.
Most fretboard humps are not due to neck resets; they are a by product of a guitar drying out. I am willing to bet that most of the folks here have seen fretboard humps on guitars that have NOT had neck resets. Ever wonder why that is?
Kostas