'Nasty' ... I would agree but none of those Defensive Units were better than good, in my opinion.
Too damn inconsistent and undisciplined given how much resources the Rams put into that side-of-the-ball.
None of the Rams' Defensive Units when Fisher was the Head Coach finished in the top-10 in points allowed.
Not one was better than 13th (out of 32 teams). In fact from 2012-2015, the Rams were between 13th - 16th every season in points allowed. That's just a shade better than League-average.
If the Rams had played top-5-to-10 Defense, even with a conservative and limited Offense, some of those seven-win seasons might have been playoff seasons.