Mocca align tool

I'm working my way through Maxon's character rigging tutorial and have a question about the align tool.

This is obviously important but the tutorial brushes over exactly what it does and how it's used. R11.5 help doesn't give any either.

It's applied to a bone object and presumably aligns the bone local axis but to what?

Also in it's use: at one stage in the tutorial the tool's selected and then applied to a series of bones in a heirarchy whereas later on the tool is selected each time before it's applied.

I'd really like to get to the bottom of this.

Thanks

Alan

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