MSOCS, thanks for the info. The Pegasus engine was definitely an impressive piece of design work at the time with its four lift nozzles. I believe the water was injected ahead of the 1st stage turbine nozzle to keep turbine inlet gas temps within safe limits. But as you noted, the latent cooling from the water injection allowed the fuel/air ratio in the combustor to run closer to stoichiometric.
I was involved with some of the early conceptual design work for the JSF lift fan. I wish people would appreciate the technical challenge of designing this huge 30,000 horsepower counter-rotating fan, gear drive and clutch system. The F-35B's shaft driven fan is actually much more efficient at producing vertical lift than the Harrier's use of compressor airflow.