Grammar, Usage / Confused by the clause ("all but / he") - help me parse a sentence [7]

"The brief makes clear that the argument presented to the court by the acting solicitor general, contending that Mr. Ashcroft is immune from prosecution and all but ignoring the disgraceful conduct from which he seeks immunity, is hardly Justice Department gospel."

I feel a little bit confused about the above sentence, especially the clause "contending that Mr. Ashcroft is immune from prosecution and all but ignoring the disgraceful conduct from which he seeks immunity".

I'm wondering who "contending that" and what "all but ignoring" means here. In particularly, what do "all" and "he", noted with red color, refer to in this sentence.

Thanks in advance.

Writing Feedback / toelf essay- Should going to class at school be optional or required? [4]

When it comes to classes attendance, should it be optional or mandatory for students? as far as I am concerned, I totally fall in line with the statement that suggests that students should go to classes forcibly.

First of all, compulsory attendance to classes help students work more effectively. Teachers' lectures usually have synthesized and well-organized information contained in several deemed obligatory textbooks, so students can save a lot of time and energy discriminating information in the textbooks. The students can also solve their doubts promptly, since they can turn to the teachers for help immediately in class. on the contrary, the students would lose their chances to resolve their problem when missing classes.

In addition, students are able to develop their team-work skills in the sake of mandatory attendance to classses. Group assignment is often an indispensible part of a class, which aims to provide group members the opportunity to work matually in a team. Only having students attend classes compulsorily can guarantee all the students take part in the group assignment.

Last but not least, from an economic point of view, if classes attendance were optional, many university resources would be wasted. It is to say that teachers' wages, maintenance of building, class equipment, and the like, have to be paid, no matter what the level of attendance is.

In a nutshell, bearing all the above mentioned in mind, it is further preferable for students to attend classes compulsorily. And I strongly believe that schools should make classes attendance mandatory in order to realize a better education ahievement.

This is the first time I start a new thread here. I look forword your suggestion for my essay. :)