Let me explain. So, when Sentinel arrived the base after the Dreads' attack with Sam telling Lennox of the whole situation, Sentinel starts talking with his "Indeed I am" line. Question: It's obviously that he was talking out loud. You can see Sam and Lennox paying attention to what he was saying. But... why wasn't Ironhide or any of the Autobots reacting to what he was saying? Normally when someone says that you'll never fail anything opposite to what you think, you'd pay full attention to what he's saying and face him forward. So why didn't Ironhide turn around to face Sentinel directly? Was he deaf or something?! He didn't show any reaction and acted like Sentinel was talking to himself and not loud and clear behind his back. The attack was treated like it was a surprise, but they didn't make it like it was. Maybe if they moved his lines after shooting would've made it better.