InstantiatedIndex does not currently support non-optimized IndexReaders.
Please test this patch using a couple of different unoptimized readers in the constructor.
did you get a chanse to try this out? It seems to work fine for me and I plan to pop it in the trunk in a few days. I think I'll have to add a warning of some kind in runtime though as it could slow down the index a bit if the reader is way fragmented.
Sorry, no, haven't had time to look at this. Looks like it's completed, great work!