In comments to this question, the asker claims to be a shared account that is used by several students in the same class.
Do we have a policy against such shared accounts? If not, I propose that we ought to have one.
Sharing an account distorts the reputation system by pooling the reputation generated by all its principals, such that the individual users get various site privileges before their use of the site would ordinarily warrant.
The shared account it confusing to other users, when the person currently operating the account does not remember interactions that the same account had earlier.
This is kind of converse to having multiple accounts for one human user. That is allowed (according to multiple meta threads), but it also only creates problems if the multiple accounts are used as sock puppets. In contrast the first of the above points seems to always apply, simply by the nature of the account being shared.
There's an argument to make that both of these disadvantages are fairly minor (in particular, that we should be above worrying about silly rep tricks). However, since it is free and easy to create (possbily anonymous) separate accounts, there doesn't seem to be any good arguments for this practice, so even these weak problems ought to be enough to disqualify it.