Districts: rectangular shape?

This blog entry is related to the poll:What rules to adopt to draw district boundaries and avoid gerrymandering? (Total: 4 posts)
It is discussing the poll topics:

Kossack Noddy wrote :

I always felt that districts should be drawn according to population and with as few angles as possible - none of this creating teeny little "spider legs" and narrow twisty "chimneys" and long, winding "snakes" intruding into other districts just to snatch up a few more constituents.

All nice, tidy rectangles. Or maybe untidy rectangles but still recognizably rectangularish - with no "fingers" digging into other districts.

There is a lot of common sense in this quote, common sense that unfortunately does not exist in practice. Thus, there is a good case for it to be enshrined in legislation.

However, even Colorado, America's most rectangular state (!!), could not be conveniently be divided in nice, rectangular congressional districts. Other important factors also play a hand: natural boundaries (rivers, mountain ridges) and existing administrative boundaries (city limits, etc.). Noddy touches on it:

I think divvying it up like the fire station districts or coverage areas would be good - they have to limit the number of residences they can respond to in the most efficient manner possible. Legislation could be the same way.

The comparison with fire station coverage areas is a good one. In fact, it brings an important aspect into play: the convenience of (or the service provided to) the voters. Districts could be drawn in a way that minimizes the travelling time between the voters' homes to the polling station.