I am SO totally NOT a Photoshop guru, though I use it extensively for photo work, title boards, cover inserts and DVD graphics and the like. You sound much more sophisticated in your knowledge and understanding of the program.
But, I seem to recall reading somewhere that using the .psd file is how layers are transferred into the project in editing software that integrates work from PS. This alone, I know, helps you none whatsoever, and I am also NOT at all familiar with Premiere.
My only experience, limited as it may be, is with Mac & FCP.
