I found this relevant text in the book "The Propagation of Tropical Fruit Trees" by R.J. Garner, S.A. Chaudri, et.al., 1976:
"Any grafting process which involves lifting the rind from the wood when the cambium is in active growth will reveal the position of the cambium, for it is in this region that the separation occurs. Some cambial tissue adheres to the lifted rind, whilst some remains attached to the wood, and much of it is moist and slippery to the touch. This cambium, whether remaining on the wood along with the other meristematic elements, or on the rind, is able to continue growth, laying down new rind on the outside and new wood on the inside, provided it is protected from the air and does not become infected with destructive organisms." (page 85)