Good notation for showing MVC interactions (i.e. Django)

[Roy Smith]

In article <mailman.4219.1325167436.27778.python-list at python.org>,
 Alec Taylor <alec.taylor6 at gmail.com> wrote:

> Is there a good notation for showing what behaviour is at each stage,
> i.e. using swimlanes?
> 
> I use BPMN 2 notation for everything, but I feel I am overusing this,
> and that there would be a more suitable one for this.

Swimlanes?  You mean like http://tinyurl.com/caqf3h5 ?  Never used them.  
Never used BPMN either.  I've found most of these heavyweight modeling 
tools to be more of a hinderance than a help.  People get all wrapped up 
in making pretty diagrams when they should be spending more time writing 
code.

I find that when thinking something through at the whiteboard with 
another developer, the most common diagram I'll use is a UML sequence 
diagram.  I drew one on the wall just yesterday.  Here's one 
(http://www.panix.com/~roy/SongzaSessionHandoff.pdf) I did up a bit 
fancier a while ago while working through a gnarly design problem.

As with most things in UML, I find the basic concept useful and don't 
sweat the details of what different shaped arrowheads mean or what 
flavor of rectangle I'm supposed to be drawing.