Biographical note: DuffieDarrell: Darrell Duffie is the Dean Witter Distinguished Professor of Finance at Stanford University's Graduate School of Business. His books include "How Big Banks Fail and What to Do about It" and "Dynamic Asset Pricing Theory" (both Princeton).

Size-discovery trade mechanisms allow large quantities of an asset to be exchanged at a price that does not respond to price pressure. Primary examples include “workup” in Treasury markets, “matching sessions” in corporate bond and CDS markets, and block-trading “dark pools” in...