AegonIV

The chain was pulled up from the bottom of the river by two winch towers on opposite banks of the Blackwater. As I mentioned in my original post, you could easily allude to the chain without actually showing it in the river - the audience would know there was a chain by the earlier set up and then demonstrating the winching/rising of the chain at the riverside and then having the sailers/soldiers realize (through panic and dialogue) that there's no escape. The fog still works to the plan's advantage but to count on it as an essential part of the plan seems sloppy as it wouldn't necessarily be a given. The show was still great, I just thought that this one aspect of Martin's original material was particularly clever and should have been included. YMMV

Definitely enjoyed the episode and on the whole I like the choices that were made regarding deviations from the books. However I do believe that Tyrion's chain could and should have been included. A set up in an earlier episode - Tyrion telling all the smith's in King's landing to begin constructing large links and assembling them would be enough to plant the concept in the viewers' minds and then the pay off would be manifested by simply showing men on either side of the Blackwater towing it out of the water at the signal. Men on the ships would only then have to report that an enormous chain was preventing escape. Not perfect, but it certainly could be done without an enormous increase in budget IMO. I could be wrong... But this is a critical story/character point. It makes Tyrion look like a masterful tactician and prevents Davos from looking somewhat foolish. An empty ship approaching an armada has got to raise suspicions in any competent commander particularly one who has survived using his wits to avoid being trapped or bought by surprise. Deal breaker? Nah. Still a great episode.