Not only isn't it easier to understand, it's harder. With collections "do:" normally means enumeration (do:, allButLastDo:, reverseDo:), but ifNotEmptyDo: doesn't enumerate the receiver.
But in Morphic/Spec/Bloc #widgetDo: is used very commonly (for DOing things, not enumerating), so it depends on the context.
I think the important lesson here is that you eventually learn patterns, so once you know what this does it's no longer less or more readable because it became habituated.