Not really. ;-))

Everything depends on the style of the session and what's usually expected. I actually enjoy some of the more "laid arrangements" when fellow musicians (and singers, if mixed session) invite you to do something yourself that might be a little different(or not).

In a fast tune session, however, you usually have to "go with the flow" much of the time.

There's a place for all sorts of arrangements. That's fine, as long as we know what to expect and act accordingly.