All career theories try to explain hugely complex interactions. Metatheories involve a lot more complexity than other theories and therefore cannot be useful within a session , unless you have the diagram in front of you and go through it bit by bit with the client. ( which might be an interesting thing to try… has anyone done this with a client?)

I agree with Katie that they could be more useful for the careers adviser for reflection after the session. The very fact that it is so complicated and all encompassing means that whatever was discussed in the session is likely to be addressed within the theory.