Why doesn't iMovie use ProRes 422 or native instead of AIC

Question

Does anybody know why apple still uses AIC to transcode all captured video streams instead of ProRes 422? And why does it transcode in the first place? Why can't they use the native HDV or AVCHD streams?
I know that using native HDV, and especially AVCHD, loads the processor with all the decoding, but it should at least be an option for high-end machines. HDV editing on FCP works fine and the storage requirements go down to between 1/3 and 1/8 of what it is with AIC and ProRes.
I think the ideal workflow would be to capture in the native format, edit in the native format when no re-compression is necessary and only render to ProRes when effects/titles/filters are applied.
Is it just too much development work or is there an architectural consideration from the development group to force everything through AIC for some reason?
Is it a licensing issue? Does Apple pay royalties for ProRes for every FCP sale? Would it be prohibitively expensive to distribute ProRes with iLife?
Obviously only someone from the iMovie group would be able to answer all of these questions but we may be able to gather some insights from the community to get a better picture.

Answer 1

I understand that the iMovie and FCP teams at Apple have been, hitherto, completely independent.
FCP was bought in - under a different original name - and tweaked from its original incarnation before being offered as 'Final Cut Pro' by Apple. See the section marked "History" in this Wikipedia article.
iMovie, however, was written long ago to Steve Jobs' specifications by Glenn Reid as a simple video editor for amateurs.
The ProRes codec appears to have been created separately from the Apple Intermediate Codec of iMovie ..probably because of different programmers' responsibilities for the separate programs ..although, under the 'Terms of Use', we're not supposed to speculate here in Apple Discussions.
HDV and AVCHD, being extremely 'compressed' methods of storing video, similar to the MPEG-2 format used for squeezing long movies onto small DVDs, cannot be edited 'frame-accurately' directly, as most of the video frames rely on data stored in other frames for their content. In other words, the 1st frame of fifteen frames contains a whole frame's worth of data, but the next 14 contain only differences between the first frame of a group and the subsequent frames.
So there needs to be a method to 'unscramble' or extract the data from the next few frames after the first of each group, in order to reconstitute the rest of the frames for editing them.
AIC is the method used in iMovie. ProRes is the method chosen for FCP.
It's interesting, though, that Randy Ubillos, now 'Chief Architect - Video Applications' at Apple, and the "onlie true begetter" of what later became Final Cut Pro, was the man who demonstrated iMovie '09 at last month's MacWorld Keynote. So if Randy's on hand to explain how to use iMovie, and created the new-style iMovie, then maybe we'll see some more convergence occur. (..iMovie has already taken on board FCP's "instant rendering", so that we no longer have to wait for transitions to be rendered within iMovie, but can see the results immediately. iMovie's real "behind the scenes" rendering now takes place during export, after after editing's finished..)