Hi Cyan,
If it helps at all - I'm seeing two therapists at the same time as well. One is in training (will be certified by about April next year) and the other is fully licensed and has been for many many years (and for the record, I got in contact with them from two different sources and they don't know each other at all).
I've yet to tell either of them that I'm seeing another person for a couple of reasons.
First, their approaches are quite different. The newer therapist (he) is more into emotional and interpersonal aspects. She (the more experienced T) is into a whole bunch of little things to the point where I couldn't even describe it!
I'm seeing two of them for another reason which has to do with time constraints. He is new, he needs clients in order to be certified and my first T was in the same program and she was wonderful so I figured why not? He's readily available when he's at my university so it's easy for me.
She (on the other hand) is under time constraints because she is through my university's health services. Currently she has far too many clients and not enough time. She really can't see me every week and I think I need it. Unfortunately, priority goes to people currently suicidal (I'm not) or currently self-injuring (I'm not really). So I see her every 3-5 weeks. Not very beneficial by any stretch of the imagination but she really is good - even if it's only for an hour in that period of time.
When he (the new T) graduates, I'll be back to one person but I don't see any reason why it should pose an issue to be seeing two people at once. (Unless they go about things in totally different ways and when you bring forth one of their ideas to the other T they disvalue it and dislike it vehdemently.)
If it helps you at all - keep doing it. If you can even convince them to share information back and forth (of course with your permission) it could further benefit you.
Specialization is meant to be helpful and if one way of doing things isn't helping you with issues that you would like support in - it is your right as a client to "shop around"" for someone to fill in the area of expertise you might need.
Hopefully I've helped without rambling too much (I do that a bit unfortunately).
Take care of yourself.