I've read the article talking endlessly about the corners as the easiest place for users to reach and I can accept that they are correct on their own terms.
The problem is that on a laptop people are used to both visual and kinesthetic cues for their action. Just as much, any mouse "gesture" effect has to leverage our intuition about physical things... when a gesture in one place (a corner) causes something to happen elsewhere (a side), it feels unnatural and is going to keep feeling unnatural no matter how many fan boys wiggle noses and say "you're doing it wrong, this is really easy no matter hard you're claim to find it...".
Edit: The point is the bar appearing on the side cues the user to go to the side, regardless of their great dexterity at going to the corner if they happened to remember to do that (as the gp actually implies).
The problem is that on a laptop people are used to both visual and kinesthetic cues for their action. Just as much, any mouse "gesture" effect has to leverage our intuition about physical things... when a gesture in one place (a corner) causes something to happen elsewhere (a side), it feels unnatural and is going to keep feeling unnatural no matter how many fan boys wiggle noses and say "you're doing it wrong, this is really easy no matter hard you're claim to find it...".
Edit: The point is the bar appearing on the side cues the user to go to the side, regardless of their great dexterity at going to the corner if they happened to remember to do that (as the gp actually implies).