The number of times some one Rep+ you does not equal the number of rep you have. I can't remember but someone explained it a while back. Say since you have 300 posts your rep should be if you take the first number and add one which should be 4 (and it is). With mine, I have 1400 posts so my rep should be 15, which it is. The Rep+ button only protects you from negative rep (I think). If too many people give you negative rep, your rep number would go down but if you have positive rep, it balances out. This is just what I THINK that I remember. Whoever explained it might have said it differently. I bet Johnny could tell you how it works though.