Gre big book Rc test 21

Recently I have been practicing RC long passages with the idea of main technique and it is helping a lot no kidding!

But this particular passage was just pure nasty

Even in the Greg’s walkthrough , he solved this passage without using main ideas and simplifying paragraphs

On a real GRE test scenario , how can one predict for a passage like this and choose to apply simplification strategy instead of main idea technique

Cause mostly main idea technique works but on a passage like this it just fails. Also the questions were super nasty with this passage

Suggestions would be appreciated
Thanks
Regards
Dushyant