Professor that refuses to fail students - should I talk with him? I am an instructor, and the head of my department is a professor that refuses to fail students. 

I found out about this situation through multiple semesters where students would complain about this professor treating them unfairly, both to other students within my classroom, and to me directly; my ultimate question is: Should I talk to this professor, who is also the head of my department?

For context:

The professor assigns a group project with 6-8 students in each group. The projects take most of the semester and each group does 2 projects at the same time. Each student has a very heavy work load for these projects and teamwork is essential. 

The issue is when a student refuses to do the project. I've heard reasoning from, the student didn't agree with what everyone else in the group agreed to, or the student just didn't bother showing up to any group meetings.

When students mentioned how one of their team members would not participate, which was only increasing the work load for other students who also had to worry about their other courses, the professor seemed to take the right action at first by talking to the non-participating student about the project and how important it is for them to contribute. 

If the student continued to argue with group decisions (sometimes they do the project their own way) then the professor would just tell the group "find something for [the student] to do." And if the student never did anything, they would still pass the course, despite never participating on the 2 biggest assignments, which equated to 60% of the grade (including participation). 

Back to my original question - 

Should I speak with the professor - head of my department - or let it go?
Personally I'd consider it worth talking to him, where 'talk to him' is defined not at 'tell him he's wrong' but as 'for your own peace of mind try to find out why he believes his choice is a good one'.