How Resistance Trait/Gear works - Clarification Request

Please SE tell us what each tier of Resistance traits do, are they a set %? And how much %?

Please impart to us exactly what "Enhances Resist _____" on gear does and if all gear with the message on it is made equal.

Please feel kind enough to tell us why some of the new gear has Resist Blind + 1/2/3/4.

Does this mean it gives you 4 upgrades? 4%? Is having one of these items equal to having four pieces of gear with "Resist ____" (older gear).