Yes, I have actually used a much easier workflow method than what you're describing (although I used to do the Premiere>filmstrip>photoshop method for rotoscoping, and it was a pain).
Instead of using Photoshop (and going via Premiere), use ImageReady, which has most of the same features that Photoshop has in creating, drawing, rotoscoping, layer masks, etc. ImageReady is a subprogram within Photoshop, that you can navigate to from the bottom of your pallete menu.
1) Choose which raw QuickTime clip you're going to work on from your captured footage files--know the name of the raw clips, rather than your FCP-assigned clip names (if they're different).
2) Open up ImageReady (from within Photoshop).
3) In ImageReady, you will be able to open up a QuickTime file! (If you only need to work on a specific portion or section from your QT file, you can specify that when you open the file in ImageReady).
4) Once in ImageReady, you can navigate through your QT clip just like you would an animated GIF, and you can manipulate individual frames, draw on them, create layer masks, erase, cut & paste, etc. You can also assign multiple layers to each frame in the sequence.
5) To insure you don't lose anything during your editing/drawing process, keep saving the file--it'll save as a PSD file, actually.
6) When you're done manipulating your clip, EXPORT it as a Quicktime file again, and then you'll be able to import the new QuickTime file into FCP.
This will save a massive amount of time on your work flow, and will avoid having to bring things into Premiere as well as avoid using a filmstrip, which (by nature of large file sizes) can be cumbersome more processor-intensive.
I hope that helps!
-Chris
