Sometimes there's no absolutely right choice of signal and you just have to think about what to communicate to other drivers -- and when, and how -- to make everybody the safest.
My commute has a weird counterintuitive situation. It's a wye on a fairly steep slope laid outlike this, viewed from the way I go (uphill):
^ S=== ^
The uphill direction doesn't stop, whether it's going right (two way onto a two way) or left (two way into a one way), which is my usual. The traffic coming downhill on the two-way has the only stop sign.
The idea that uphill traffic has right of way is familiar as an off-road custom (I guess the rationale is that they might not be able to get going again, but downhill traffic always can). But it's a weird enough intersection that I choose to use my left-turn signal... and to be especially alert and ready to romp on the brakes if using my right of way starts to look like a really bad idea, which usually means that someone on the right and headed downhill hasn't picked up the stop sign or is in a truck with nice toasty brakes.
There are just some intersections that call for judgement calls. My previous commute involved a five-way (nearly an eight-way, and just a short distance from another confusing intersection with a large hotel). The five-way involves a traffic signal for the main crossroads (busy streets both), and stop signs for everybody else, and a spiderweb of pedestrian crosswalks that actually get used and a couple of businesses with driveways and parking lots in the triangular and quadrilateral islands strewn through there. It's always a good question just when and where to start signalling so that people know you are (say) about to take the second, chickeneyed-angle left rather than the first, 90-degree left.
And that's when everything is being used normally -- I once saw somebody BACKING UP through almost the whole thing after changing his mind. I'm sure it is no conicidence that on the far south side of this ganglion of congestion and confusion is a fairly prosperous-looking paint-and-body shop.
Sometimes I think cars need some additional turn signals: * 45-degree arrows ("I'm taking the big left, not the small left") * U-shape (self explanatory) * Circle of outgoing arrows ("I'm confused and aggressive and bulling my way through--you guess where") * Circle of inward arrows ("I'm confused and rather pbuttive and likely to stop and think about it at the most dangerous or at least clogging point available to try and get my bearings") * Random sequencer ("I'm confused and pbuttive-aggressive and will soon dart off in a direction you wouldn't guess from whatever turn signal I was using anyway") * Omnidirectional rooftop beacon ("I'm blowing the red light--if you're not as important as me, get outta the way!")
Then again, people can't seem to use the standard ones...
--Joe
