What utility does the Tau bond model of orbital overlap have?
Tau-bonds provide an alternative valid description of electron density in alkenes and alkynes. Even in the modern chemistry
A good example is the conformational preferences in propene (lower energy of the "eclipsed" conformation). You can find more information here: http://pubs.rsc.org/en/Content/ArticleLanding/2011/OB/c1ob05393k#!divAbstract