I read that Tony, Herbie and Ron would have in-depth discussions post-gig about concept and ideas but if that lasted through this era or even 67', I have no idea. But either running math problems or just having fun are both inherently selfish in a sense, you can do both of these by one's self and neither are destined to create a connection either with bandmates or an audience. Who knows what Tony was thinking, but he had a special gift to take complex drumming concepts and make it a musical idea and not sound like a practice room exercise.
Just my 2cents - I think a drummer or any musician can create an environment to keep the flow that is both cerebral and instinctual. I used to do a lot of improvisation exercises with a collective group and it got me both in the mindset of composing and improvising (which are really the same thing IMO, improv is just spontaneous composition and composition is a organized collection of your best improvised efforts). One thing I did with writing was I tried to give players a vehicle for creativity. For example it may be a theme/melody or something conceptual but challenging...but I wanted certain limitations so they could find creative solutions and dropped any preconceptions once we are 'truly improvising'. It was the equivalent of putting a black hood on my bandmates, throwing them in a white van and driving them to the middle of now where and giving them a tooth brush and flashlight as a tool to survive and see what happens. One simple thing anyone can do is tuning which is something I...well, not 'think' because that is a dirty improv word but lets say 'be aware of'. Not in sense of pitch or drumkeys but rather empathetic listening; tuning your performance to the room, the dynamics of you perspective and what you sound like on the other side of the room, and of course the space to create and fill ideas or play with your bandmates ideas. I think one has to enjoy the art of conversation....if you are a person that talks about yourself with your favorite anecdotes but not looking for a human connection, the music shows. It why it's my favorite art form, it really cuts the crap of who a person is (for better or worst).