Why and How we Underlay and Overlay
Underlaying and overlaying are two crucial laying techniques used on more advanced offers, most notably; existing customer refund offers.
I have written a conclusive guide on what exactly underlaying and overlaying is, when to use each technique and how you would calculate each of them.
Their main purpose is to take 'non risk-free' existing customer offers and to turn them risk-free.
For the complete guide, click the link: