I thought the reason for booster shots was not to remind the body what the antibody looked like (in the case it forgot); but to make the body 'more aware' of this disease. For example, if a disease is a particularily vile and fast incubating bug; having a 1x immune response may not be adequate to prevent an outbreak. Simply stated, the body will fight off the infection, but not as quickly as would be required to prevent irrepairable hard from occuring (such as Polio).
Thus, the booster shot was to create a synthetic response for the body to have a 2x immunity reaction to this particular bug, instead of only having a minor one. If we use Polio as a potential case; the intent may have been to make the origional vaccine so weak (as to prevent the vaccine actually creating the disease) that the immune response, while present, is relatively minor.
If the body 'forgot' antibodies; then it stands to reason that there would be common reinfections of 'Chicken-pox' where most of us will only experience the joy just once in our lives.
It gets very complicated because our immune system is very complex. It is not as simple as forgetting antibodies. The strength and duration of the immune response varies depending on which pathway is used. The are multiple types of cells and antibodies in our immune system. I will forward you a few good links later, if you would like some more background.
Also, there are common reinfections of chickenpox. It is called shingles, which is caused by the same virus. The disease presents itself differently once a person gets chickenpox. A person can also get shingles without having chickenpox if they have had the chickenpox vaccine!