It's certainly one of the most commonly used cliches on message boards, in the absence of a properly explained counter argument.
For the overwhelming majority of the past two years (at least), the system has been very successful, so the definition of madness would actually be to completely abandon something that has worked more often than not. The sensible reaction to the struggles of the past two months or so should be to tweak the system and personnel until you've addressed the weaknesses.
Even if we did decide to change our way of playing dramatically, that change would still need to be introduced very gradually. One of the big factors behind our decline and relegation to the non-league was the habit of upheaving almost the whole squad every summer. Whatever we do from here, it needs to be evolution, not revolution.