Songs bulked up well, he seems both stronger and fitter.
I think the clubs learned a bit more about how to get players in shape for the Premiership. That transition period after the invincibles was a team of skinny weaklings. The likes of Hleb, Reyes, Rosicky, teenage Cesc, etc Now even the small guys like Walcott have bulked up and added the muscle you need to succeed.
Don't know what the deal is with noodle legs Gibbs though. He needs to get on whatever weights plan Theo was on when he bulked up that time. And you'd think being injured so much it'd give him that opportunity to build mass too. He badly needs it, it'd help him to fight off the injuries a bit more too.