Why are people so critical of PJ?

[Eomer of the Rohirrim]

I think Jackson has done a tremendous job and he has my respect.<P>However, I do find some things quite strange about his movies. For example, the scenes of the Middle-earth landscape and the activation of Gollum was amazing, as were so many other aspects of the movies.<P>But he brings the movies down quite a bit (and the splendid aspects of the movies do not deserve these burdens) by letting in some ridiculous scenes, such as 'Aragorn-falls-off-cliff' and 'Denethor-jumps-off-city'<P>Bits of the book that really don't need to be altered have been altered, and this is why Jackson gets stick. Let's be honest, the guy was going to get criticism anyway because the project was so massive.