Pretty good qucik guide for noobs.
However I think part 2 is slightly misleading/confusing.
1-You say it's better to have one large vis-leafs. Obviously that's not the case, but after that you start to explain why it's best to have a large one in that room with columns. That all makes sense, but the first sentance almost seems like you mean the entire level should be one leaf.
I think just clarifying that better would help. That it's better to have a fewer large leafs in an area than multitudes of tiny leafs.
2-The next sentance says you will use a hint brush to fix it, but then you skip right to func_details.
You should probably change the hint sentance to func_details to fix. Because then you change the cylinders to func_details.
3- towards the end you say having alot of small leafs can be fixed by hints. In actuality hints would make it worse, I think you are just having hints/func_detail confusion.
probably just got sidetracked in that tut section.
So I'd recommend pulling all hint stuff out, place it after the explanation of func_dteail in it's own area.
The true reason for hints is 'to make more leafs' so you can minimize views where Hammer fails to.
Also, when you get around to telling how to make a hint you say to use a 1 unit wide brush. While that works it will create 2 extra leafs. One 1 unit wide inside the hint brush, and the new one you used the hint to create.
You should drag 4 of those verts together in the 'skip' side and you'll have a pyramid hint brush. That'll only make one cut and one new leaf per hint.