You are getting down voted likely because you have recommended a site that has been caught shilling their wares here under the pretence of sharing something when they are in fact selling it. This was done using multiple accounts.

Regarding the actual content of the site. They were selling the DrumCode Production PDF for something like $50 at one point. Here is a comment from somebody who paid for it who posts in this sub regarding it.

A few months ago the site abletonbible sold it. It was like 5 bucks for a small period of time, that's how much i would pay again. Some tips were usefull, but the DMP Techno Course (https://www.dancemusicproduction.com/products/drumcode-techno) covers all the things mentioned in the book much more detailed, so maybe have a look over there (techniques like Hocketing, Syncopation etc.). I actually read the book first and thought that the guy at PML wrote it because it's so similar but much more detailed.

The guy paid $50 or something but feels like its worth 5 and then recommends another site. Thats not good.