Can someone explain Inspiring Bond?

I'm using Pohx's RF guide and towards the end of the build, he recommends to pickup Inspiring Bond.

Inspiring Bond states: Link Skills have 20% increased Buff Effect if you have Linked to a target Recently
10% chance for Energy Shield Recharge to start when you Link to a target

What does "linked to a target recently" mean, and how do I "link to a target"?

Link skills are just subtype of skills, you can “connect” to another target to give it bonuses.
https://www.poewiki.net/wiki/Link_skill

Recently just means 4 seconds most of the time in poe. So it basically means “if you used this type of skill in the last 4 seconds”

Where does Pohx says this? Cause I can think of 0 reasons to use this interaction with RF build. Maybe it was “inspired learning”? Or “inspiration support”? Or maybe there’s a timeless jewel that modifies nodes?