Activator performance improvement

Shouldn't close the previous PR early. Turns out I did not have to change much of my design.

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@pranavkm
@halter73 
@rynowak
@ipjohnson
@yishaigalatzer 
Since you're making tweaks here, might be nice to update this code to be `!givenMatched`. There's similar odd usage of `bool`s elsewhere in this class.