We'd be interested in hearing about your convergence and timing experiences when you run largish jobs (even sequentially) since this type of problem comes up relatively frequently and we do need a variety of solvers that can handle it while currently we do not have great tools for it.
Of course I will keep you in touch with the results of this 'ainsworht' approach! I also plan to compare it with the new 'GKB' approach of PCFIELDSPLIT.
Many thanks, Olivier
