i have a bunch of previously captured HDV clips shot using the FX-1 which were captured using the AIC in iMovie. can i just drop these into an NTSC Anamorphic Final Cut Pro 5.1.1 timeline and render to use in an anamorphic DV project? or is there any point to re-capturing downconverted footage from the camera?

I dont know about FCP for I use Vegas. I have found that the quality is better when downconverting in Vegas---others have found the same.

i have a bunch of previously captured HDV clips shot using the FX-1 which were captured using the AIC in iMovie. can i just drop these into an NTSC Anamorphic Final Cut Pro 5.1.1 timeline and render to use in an anamorphic DV project? or is there any point to re-capturing downconverted footage from the camera?

That should work.

You might also try importing the clips into QuickTime Pro and converting to DV first. It will make editing easier as the files will not become un-rendered everytime you change them on the timeline.

can i just drop these into an NTSC Anamorphic Final Cut Pro 5.1.1 timeline and render to use in an anamorphic DV project?
Yes. I've used HDV from a Z1U to do just this.