It sounds like it may be useful in some way.
As another poster just said, it reminds me of a sort of 'shock' routine that some bodybuilders do to break through a plateau and create new growth.
He said that after he had done his edging and came, his girth was about 4 1/2 inches, but in the 20 minutes afterwards it ballooned up by itself to over 6 1/4 inches.
It's that bit that sounds interesting to me.
It's as though after he came, his penis shrank down a bit which sounds normal, but afterwards his penis appeared to want to expand to a size that's much bigger than usual.
And that pump lasted 2 days.
6 hours a day sounds a bit much, and is bound to make somebody over obsessive or simply burn out.
But...maybe this technique could be used once every week, or once every two weeks.
Definitely something to think about.
The way that he described his penis ballooning up over 2 inches afterwards, after he had ignored it and left it alone, sounds interesting, and it would be useful to know what's exactly going on there.