(1) completely agree with the 2nd point - work consistently / intentionally. It’s really easy to waste a year (or 2…3….more) once you are in the ‘do research’ phase.
(2) I don’t think he was specifically saying ‘write your dissertation’ for an hour. Use this writing to organise your thoughts, plan the next steps, argue with your imaginary committee, plan your Nobel Prize summary of your field, etc. THIS will certainly support Point #1.
(Full disclosure: I didn’t follow this advice, but wish I had….I was one of those ‘hard working’ PhD students … but I got better at crossword puzzles!)