Would be nice I agree. For now I believe your only option is to use Twixtor AVX to do straight deinterlacing / interlacing. Unless it has changed the AE gasket thing did not work properly with effects that collects fields at other points in time, however if you have Boris FX I think you can indiectly use FieldsKit via running Boris.
Thanks Pierre. We have been using 3Prong's SpeedRamP plugin for de-interlacing so far, but although its a great tool, its not RT and also not really designed for the job as much as Fieldskit is.
There is a workflow issue with Avid progressive projects when you need to work with interlaced source footage. In PAL land people will often choose to work in a PAL 24p film project and although most footage it progressive source, often they will incorporate interlaced 50i source. The final output is 24fps film, so working at film speed is crucial.
When playing this back to an external monitor, the standard 12+1 field PAL pulldown (24fps - 25fps maintaining film speed) results in a very nasty frame jitter due to the interlaced source being put completely out of order. The progressive source reacts fine to the 12+1 field pulldown. To fix this the interlaced source material either needs to be de-interlaced or drop one field.
At preset the only way to do this is with SpeedRamP AVX (non RT), Boris Continuum Complete ($800) and Genarts AVX 2.0 ($1800). Please, please Re:Vision, develop FieldsKit to an RT AVX!