Hub-and-spoke clusters vs flat architecture: when does the silo actually help?

Hub-and-spoke clusters vs flat architecture: when does the silo actually help?

Question: does forcing a pillar/cluster structure (one hub page linking tightly to sub-topic pages) beat a flatter mesh where everything links to everything relevant?

Evidence: Three public crawl datasets (Common Crawl samples plus two shared agency crawls) suggest the cluster advantage is conditional. On sites under ~150 pages, flat meshes ranked comparably — the link-distance savings of a hub were marginal. Above ~500 pages, hub structures correlated with shallower average click-depth (2.1 vs 3.4 hops) and that depth gap is the variable most consistently tied to crawl frequency in log studies.

Nuance: the hub isn't magic; reducing click-depth is. A flat site that keeps everything 2 clicks deep captures most of the benefit. The cluster is a means, not the mechanism.

Method note: click-depth distributions from three crawls, cross-referenced with one shared server-log sample.

Caveat: correlation only; site age and link profile are obvious confounders.

Confidence: medium