There is a definite difference between playing time and playing within the time. To illustrate, let's look at a couple statements with which I think everyone reading this will agree.

First: Every musician should be able to play in time. And: Not every musician is able to play in time.

Now, a controversial statement, but one I think you'll also like: The drummer shouldn't have to keep time for the other band members.

Personally, I don't play time. When I started studying drums I was never taught to do that. I play parts, colors, phrases, et al, but "in" time and "within" the time and I believe that is due to my musical upbringing.

I was raised on classical music and started playing piano when I was four or five years old. After gaining some expertise with the elementary books I started playing with a metronome. My older sister, who wound up being an Eastman graduate, also worked with the metronome. This led me to the conclusion that all musicians used a metronome and could keep their own time.

When observing symphony orchestra concerts, I noticed the conductor set the tempo and kept the time. The different sections of the orchestra followed his lead. Especially notable was the percussion section. They didn't keep the time but played their parts within the tempo set by the conductor. Because of this, I never considered percussion players as being timekeepers but rather other musicians in the orchestra playing their parts and making their contribution to the whole.

Fast forward to observing big band jazz. It seemed to me the same thing was happening: the conductor set the tempo and kept the time with the baton. It seemed the drummer was playing his "part" the same as the other musicians in the band were doing.

By the time I progressed to more improvised jazz like