Someone asked a very interesting question, can I modify "NFV" to work with bonds? I don't know, I have to think about it. One thing that occurred to me immediately is to use the difference between SPX and NFV as a predictor of correlator of bonds to equities, since bonds and equities have a known intermarket causation on each other. But that would not explain, only give statistical correlators which probably not give us edge.
If I can make it work on an atomic level the way NFV does for equities, it would be a kind of unification of markets, and as this person pointed out, the liquidity is immense and opportunity would be greater.