He's been pretty hit and miss of late, but his earlier books are almost all thoroughly good reads. I found that I had to read them in the right order though (not chronological, but by characters), I started with the City Watch, moved onto the Wizards and then the Witches, then finished with all the one-off books.
I don't hold him as a standard of great technical skills, but then again even the great books from great authors show remarkably little respect for 'the rules'. But what he does do is show remarkable restraint from overusing any single construct. There are authors who will use emphasis of some kind with alarming regularity, to the point that they stop being useful as a means of impact.
He also shows a willingness to drop his signature traits (lack of chapters, lots of footnotes etc) when appropriate. For example, Going Postal is the first of his Discworld novels to have chapters. The Thief of Time is the first book to do something other than a line break symbol as a means of changing scene. For an author as prolific as he is, the fact that he's still trying new things is a good thing (I think).
tl;dr - I don't object to authors breaking 'the rules', but I like it when they break the rules for a reason, not out of laziness.
Detty. Professional Expert.
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