User blog comment:Master Sima Yi/Assassinews 28-02-'13 — Assassin's Creed IV: Black Flag revealed/@comment-5174994-20130305184202/@comment-4999424-20130305193333

No, he uses portals

As a serious awnser: the liks(the Q&A, the trailer, the screenshot and the interviews) in Simas other AC4:BF blog confirms it.