In actuality it isn't the cool people that can talk and sip a drink at the exact same time. But those who're willing to spend the time to hone and perfect that difficult skill. ... I've wasted my life.
Something else that's difficult to master, is coming up with new interesting ways of trying to fool you into following my Twitter feed!
Well, in comics people can drink and speak at the same time. Because it can be assumed, that since the speech bubble can be pretty long and the picture is purely static, that there is a window of tolerance what is happening before the picture, on the picture and after the picture. If this was a movie, the picture would represent one frame happening around the time the speech is happening. But what I don't get that in most comics, two people who speak with each other on the same panel have both their mouth opened simultaneously. That implies, that they both speak at the same time.