You may not hear them talking, but believe me, 99% of their actions are performed after a checklist prompt from the other person, and each is absolutely certain the other KNOWS what they are doing before they do it. There are absolutely NO independant actions taken in a cockpit. Or there shouldn't be. I know in the Navy/MC, for example, even if they've lost intercom, they will write down things and show one another, use handsigns, scream, whatever it takes. And during an Emergency proceedure, say an engine out requiring a prop feathering, they will have the PNC reach to the appropriate feather lever, receive verbal confirmation from other pilot, THEN and only then pull it into position. They will then reach for the fuel cut-off, and not until they receive confirmation from the other person will they pull it, even if the engine is burning merrily away. The same is true of commercial planes, although procedures may differ slightly from company to company. The basics remain the same: Checklist or command callout, verbal confirmation, action taken, verbal confirmation, and response. Say, for example flaps during landing: "Speed 210, flaps 15","roger, flaps 15", move flaps lever to first detent. "Flaps 15 set and moving", "Roger, flaps 15 set"
All this seems a tad unwieldy, but it's important, because it prevents errors that could cause severe repercussions, missed checklist steps, etc.
Like I say, in a simulator environment, without an AI second person in the cockpit, things like this don't happen, but in the RW, I gar-un-tee you they are done like that. Basically, in a simulator, one person does it all, so a lot of the give-and-take of a cockpit's communication procedures is missing.
My Father was a UAL pilot and Captain for many, many years, and I listened when he and his friends, people like Mr. Lear, and several pilots, etc from various airlines would get together and talk, whether during parties or just a chat. I learned an awfull lot that way, and I was even permitted a few 6-month refresher training classes when my father went. These included a lot of sim time (Much bigger and more complex than my FS9!) practising emergency procedures, etc. I had a blast

Ok, I'll stop babbling now. Sorry, just a subject near and dear to me

Pat☺