Well 3rd season was when I tuned out. So...
There was just something about T'Pol's backrubs on Trip, and episode teasers trumpeting the fact that next week Archer would use harsh interrogation tactics on an alien (rather then, I suppose, keeping quiet about the fact and letting us be "shocked"... use of quotation marks most definitely deliberate), that convinced me the show was just too desperate to possibly know how to fix itself. And I tuned out.
By the time of fourth season, I had already forgotten to remember, week after week after week, what day it was on. Just because I'd gotten too used to not watching the show. Plus I wasn't plugged in enough to know what weeks marked the beginning (as opposed to middle) of any particular story arc that people were talking about.
So... since they lost one viewer, I would say the approach hurt more than helped. I'm no stranger to serialized television, it's the reason I gave up on VOY and stuck with DS9 (which I later missed in favor of B5, just because college wouldn't afford the time to follow more than one show). But when ENT tried their crack at it, they were desperately reacting rather than being inspired. And for me it showed.