Storage spaces & maximum number of columns

I swear I read somewhere that Microsoft recommends using one less column than your possible maximum for Storage Spaces.  For example, if I was using three-way mirroring, enclosure awareness, and 15 SSDs spread evenly among three JBODs (5 SSDs per JBOD), then I should only use 4 columns (instead of the 5 columns possible).

Is this a valid recommendation from Microsoft?  Has anyone actually done this and what was the result?

Thanks.