If you look at HNPG history above, when number of Buy flags were more than Sell flags, the market next day was up and down otherwise.

The only time the market was down although Buy flags were more than Sell flags on 9/30/19.

So the total accuracy from lat 4 sessions: 75% (3 out of 4)

Also someone who already started to follow the HNPG process might want to consider to set stop using System's DH and DL. I don't have firm data to show if this would be beneficial. However I feel like it would have a potential advantage.