IMHO shield gating abuse is kind of a boring mechanic, and mostly unnecessary (unless you're going for multi-hour survivals with enemy levels goings into thousands). I'm a veteran player and between spoiler mode, adaptation mod, warframes with damage reduction and now archon shards I never feel too squishy even for SP or archon hunts.

If you want to use it feel free to, just wanted to point out that it is by no means a requirement to be good at the game.

It's probably best explained with a video, but the idea of shield gating is that when your shield breaks (hits 0), you get a brief window of invulnerability. If you can consistently use that window to restore you shield, you'll never die. Easy, right? Rolling guard can extend that window, as well as purging any status effects on you.

It's an active playstyle, requires specific builds as well as never running out of energy, and if you screw it up you're dead, but it will take you all the way to level cap if you do it right. Personally for archon hunts I just run a tank frame.