thats what Jimmy Page did too, except he usually barred the two strings on the A and D or D and G or whatever

thats what I do, and i remember it taking kind of a while to get the hang of because my pinky is rather weak

but it makes switching power chors a ton easier

also it lets you switch to chords like this really easily

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----5--5--5--5---
----3--2--3--2-----
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