Oh, but here's the thing. I am on a CX OneWorld F award which requires at least three airlines. BA from LHR to NRT, JL from Tokyo to Osaka (in Y only because it's domestic, and I am a bit afraid about booking JL flight right now.), CX from KIX to HKG and finally CX from HKG to LHR. There are currently no availability from HND to ITM for the three days that I am looking at. If it wasn't for the ticketing criteria I would have taken the bullet train like you guys are suggesting.

Thanks RichardInSF, I'll check out those options online.