The Flip-Side
You've clearly expressed the Flip-Side of modifying every application to "fit" a certain job. I think this is all intentional smoke and mirrors, since many of the jobs I see people have (The good ones, of course) are had by someone who knew someone who knew someone that could have their resume considered...or through a recruiter of some sort.
Since many jobs don't have a real hiring team to fulfill the job, the least qualified, most FOS candidate gets the job because their drive is different than the person who may actually do the job well and enjoy doing it.
In the end, although your strategy isn't a bad one, it sure is time-consuming...and by the looks of things, even following their guidelines to a "T" has not rendered much success...
Is this a fair assessment?