b techs dont have it so bad. at my dealer last summer, c techs didnt exactly do shit work, just kind less thoughtfull stuff. they usually hire a kid or something to do lube jobs, but everyone does them…at least where i worked.
a techs tend to do the harder jobs, finding electrical faults, pita complaints ( car makes slight rattle when its 23 degrees out, over slight bumps on left hand turns… intermitent faults.)engine work, but our a tech did have our service writer by the balls, so he would, and was able to deny jobs.
b techs do alot of hard work but not as hard as the a tech, emissions faults, evap leaks, brakes, also diagnosis
c techs, do a lot of jobs that dont involve alot of thinking, brakes, tune ups, warranty, suspension, tires
but that was just one shop, everyone did everything, just some did certain jobs more than others. i did a lot of inspections, brakes, alignments,and oil last summer…its not so bad, but i was paid hourly.i also got to help out the guys who have been there on harder jobs. i helped out a tech put a cluth in a new c6 
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