Hey James,
It'll probably be easiest to consolidate our conversation to one medium. Since this is visible and may prove useful in the future, I'll leave my comments to your most recent email to Presales here:
The development teams are in the process of working on the searching capabilities. In particular, work has been done on adding clustering support to LFFTS and we hope to provide that in the next major release.
In terms of the threads, a single search uses a single thread. Concurrent searches will each have their own dedicated thread. In general, one the number of threads equals the number of physical cores available, that's where we'll start running into diminishing returns.
I'm very curious to hear more about the solution that you proposed regarding the multiple queries across different repositories! I'm not aware of any development like this internally, but depending on the feasibility and performance gains, it sounds like it could be a promising idea!
Unless you have any objections, let's migrate the discussion to this forum so we can have this as a reference to work with in the future. If you'd like to continue the discussion privately, as to avoid the distribution of certain details, just respond with any comments or questions to the Presales inbox.