Quote Originally Posted by Steely Glint View Post
They deployed their infantry *outside* of the castle. Like, why even have a castle if you're going to do that? Then when they got their kicked and a bunch of soldiers killed for no reason they retreated inside the castle anyway, meaning the only thing deploying outside the walls achieved was that then had to light the trench during the fighting, which would have failed completely if Melisandre hadn't turned up.

The Dothraki Suicide Charge can be written off as a simple miscalculation (It's not like worse mistakes haven't happened in real history), but their entire deployment at the start was the work of a complete madman.
The infantry outside makes sense if looked from the lens of slowing them down. They fight, hold the line, when they can't hold anymore they get to the trench. The trench is lit and as long as it burns the undead are blocked (well then they did the dead body bridge). Then they hold the gate and castle wall. Limited space on the wall itself so troops would just have been sitting in the courtyard. Also gives time for the archers on the wall to shoot more shit.