Due to recent infractions of this rule, it seems important to restate it.
Just because the mud lets you do it does not mean that you can/should do it.
Here's a recent example. There's an area associated with an organization. There are guards at the entrance of the area who make it so that only organization members (and their guests) can come in. Inside, there are shopkeepers that are not program-restricted because the idea is that they would sell not only to the organization members but also to their guests.
Teleporting in to avoid the guards then proceeding to go and buy things from those shopkeepers is NOT allowed. Considering that there are guards at the entrance, I would think that the shopkeepers would think better than just sell things off to people they do not know, unless those people are accompanied by known members of the organization.
That's one example where some simple thinking can help you easily determine that the code lets you do something that you wouldn't be able to do in that imaginary world, were it real. That is exactly what "code abuse" is.
And yes, I know that you can pretend that you disguised yourself to pose as a member of the organization, or that you used your elite charisma to bluff your way through the shopkeepers ... but those tricks have a good enough chance to fail that they shouldn't be used without imm supervision; that is, you shouldn't just pretend that they automatically work and go ahead with them.
If you recently used teleport (or any other teleportation spell) that way, do not be surprised if the next time you log in, you see
teleport ... <unknown>
on your spell list.
