CHG: Syntax suger

Experiment:  unfolded a loop.
Experiment: speeding up "Hf mf nested"
CHG: removed some default keys from "hf mf nested". It wasn't being used anyway.
CHG: changed the way "hf mf nested" reports back keys
CHG: "hf mf nested"  and "hf mf chk"   now prints the key-table.
CHG: changed the output list for "hf mf chk"