Not all officers are traffic enforcement, so depending on how he got your speed, it could also be the case that he took all your info to pass it along to another officer to issue a ticket. At times they don't even have a ticket book in their cruiser.
If that is the case, then both officers will have to show up at court to testify.
This is a very rare case, the officers words that I was speaking to was "if I really wanted to press the issue, I can radio another cruiser to the scene to issue a ticket"
As a driver one would have to do something really crazy to tick off an officer to go to such lengths, but that is just my opinion.