The discussion about using frames of animation for flahing was specifically for solid color flashing, and NOT invisibility flashing.
The whole point of behaviors is to reduce the need for events. The whole point of Construct is to reduce production time and let people spend more time and energy being creative with the least programming grunt work.
I'm glad Ashley is making the already useful Flash behavior drastically more useful. Saving our time and effort so we can make better games faster ad with less events is never "entirely unnecessary"...in the same way that Construct is not "unnecessary" because we have C,Java, Action Script, Basic etc.