There's a difference between being aware of the Captain's flows and watching him out of the corner of your eye vs. having to do it yourself.
Your job requires backing the Captain up. That's not the same thing as doing it yourself. Know what you expect to hear. Don't ignore the other guy's flows/call outs but don't go crazy trying to be able to generate it yourself. Figure out that mental sweet spot and you'll do ok.
Even with years, or thousands of hours, on an airplane I couldn't necessarily generate the flow, or verbiage, that FO's do off the top of their head. But after years, or thousands of hours, it was obvious when they'd missed something - "whoops, we missed something."
And the speed is also important. If you're much faster, or slower, than the typical range it can throw the entire cockpit flow off.
One a/c had about 5-6 distinct clicks after engine start that the FO did. One FO did it as a speed test. I told him that it was better for me if he slowed down a bit because I actually got used to the sounds and motion the FO's did which made it easier for me to give the panel a quick check. When he did it so fast I had to stop and look over each switch, in the flow pattern, to verify what got done. "You're not the first Captain to tell me to slow down." There's a balance.