Yes but composition is about where objects sit within the frame. Timing (getting the subject where you want them by having quick reactions and an aesthetic sensibility) and time (the freezing or otherwise of such subjects), are two different things. A river in the bottom third of a shot will have the same influence on the composition whether your exposure is 1/1000 or two hours.
i see what you mean, i guess i am talking about TIME, not TIMING
TIMING is when things appear in concert ( or not ) in a frame and that is different than TIME ..
time renders objects differently depending on the length of exposure ( texturally and aesthetically ) and it seems to change the composition of the frame
whether it it is a long exposed streetscape, seascape or even portrait ...
to me at least composition isn't just static elements, but fluid elements as well ... and if something streaks across a frame, or has no texture, or a lot of texture,
it completely changes the composition of an image ... maybe it is splitting hairs ? ( i think i am talking about something completely different than you )