Talk:Sentinel's Mark

what's meant by stepdown?

I stumbled upon the remark "stepdown" in the article. It's nothing about "to step down [voltage]" or about to step down (=retreat). Other meanings aren't offered in my offline or online dictionaries. So the intention of it remains unclear, for me at least. Are there native speakers among you who can explain in a convincing manner what it means and what that remark was intended to tell us? -- Bwijn (talk) 12:49, 10 August 2015 (CEST)