|It is possible that he has extra time on his hands because he does not have to keep repeating himself and correcting problems that occur because of inadequate communication. Many communication experts today emphasize the importance not only of redundancy in the communication process, but also the importance of communicating messages using several different channels. |
It is also important to take an honest look at your performance. If some of your assignments have fallen through the cracks, then perhaps he is simply trying to patch things up.
On the other hand, if your work is uniformly excellent and his email is voluminous, then you should meet with him on a businesslike basis and let him know that you can save him even more time if he were to thin out or even eliminate some of his email to you. You can suggest that he do this on a trial basis, and then the two of you would jointly evaluate the results.
It is also possible that you are dealing with a compulsive and insecure manager who has a hard time letting go of anything. If this is the case, the long email notes are here to stay. You need to look at the overall job and his overall managerial style to determine if you are here to stay as well.