HyceThe idea is the corridor allows players arriving from choke or cave to have a safe route to a high ground on mid that is not the house or bridge, allowing more than one good way to approach the mid. Before the only good option was going to house and then across the bridge.
that house only have one way to exit on mid (both from choke or cave push) which ends in a pretty blind spot
http://i.imgur.com/nhJpMRo.jpg
honestly, who would push from here? roamers could do slaughters if combos come out from here, it's a trap, and also if the rest of the team can't hold house and/or the bridge, you'd be flanked easily, in case you push all the way out from cave, there might be a chance to accomplish the push, still, but if you come from choke, there's no way on earth you could go inside that without getting destroyed, or in any case there's no way to win the push, unless the opposite team is blind or have some kind of handicap
edit: well actually, my fucked up mind translated "The idea is the corridor allows players arriving from choke or cave..." players as players who are pushing, combo, etc. If that's supposed to be a flank, used by scouts or roamers, it's not a bad idea, but as a flank it's kinda too exposed and visible and ends pretty much in the opponent team's face