He was covered in blood, in serious medical condition, pretty much exhausted. He was at the end of his rope. He found a boat, but he pretty much could've found some concealed bushes and nobody would have found him until they smelled the corpse.
I don't even think we can call them sophisticated terrorists. They knew how to make homemade bombs, but I don't think top of the line terrorists are going to start robbing 7-11s, shooting cops, carjacking strangers for their ATM money, etc. two days later. They either blow themselves up with the bomb or have some plan of how to fade back into the woodwork. My sense is that there aren't a lot of grand lessons we can take from this ordeal. Hopefully the only lesson is to would-be copycats - that there are too many video cameras and picture-takers out there these days to slink in and out of crowds unnoticed.