No you've got it all messed up in your mind, the + and - are for increasing the age of boobs, the minus can revert boobs back to original after medical enhancement and at your desired level of perkiness. The benifits are great, when she leaves to go shopping you can take it to either extreme, give her no tits whatsoever or give her a set of 99 year old tits that drag along the ground. Then when she comes home you just put them back how you like them.