I used PHP for five years professionally, I consider myself as well positioned as many to have an informed opinion about PHP weaknesses and strengths. My diagnostic is that PHP weaknesses are structural, and no amount of guidance can fix that. If facing the choice, one should not choose PHP over other solutions. (It happens also that I am working in Chinese tech sphere, where many startup choose PHP just because it is used by Facebook and Wikipedia, which is really sad.)

However, I appreciate very well the need for such a guide when you have no other choice. I did not read all of it, but it is certainly necessary to have strong coding conventions and a defined set of "must do/musn't do". I remember we had even built a code checker that was forbiding the use of many php functions and syntax, and had a set of wrappers around basic functionalities like string functions or date functions.