We've seen planning from Cho, the Aurora shooter and Columbine shooters that showed some sophistication.
Sophistication? Interesting classification for such shooters. If a rampage shooter shows any time of planning, they are sophisticated?
I am 100% certain Charlie Whitman and Sylvia Seegrist, the Columbine shooters, etc. had not see such videos because they weren't being made back then, but they had their own forms of sophistication. Robert Wayne Gladden, Jr. was supposed to have been quite sophisticated because of the way he snuck the shotgun into school, but beyond that, no big plans.
Suggesting rampage response videos are teaching these people are like saying violent video games are teaching these people. Having a bit of gear and some tacticool accessories or homemade bombs. You could get the same input from Hollywood movies.
Some bad guys are more difficult to deal with, no doubt and it does seem to just about throw the cops completely out of their comfort zone when the bad guys show any particular skill, talent, or planning, but that is the nature of the beast. Some are going to have it. Some always have.