wrote:
Here's the setup. Making left turn at signaled intersection. Slight
downhill to intersection, then flat. It's a T- intersection, the
options are left, right or Rubio's Fish Taco's straight ahead (#1 for
San Diego denizens). Postal collection boxes on corner at right. I'm
roaring down for a left turn, but the light turns yellow while I'm
about 25 or 20 feet away from the intersection, so I brake (both hands,
didn't signal the stop there, my bad on that).

You aren't required to signal if you need both hands to control your bike.
I know I wouldn't try to brake hard with only one hand.

Mom the driver then points out that cyclists turning left go "all
the way to the left." I look down -- center line of bicycle is about 18
inches from the double yellow.

(a) Who says they "go all the way to the left"?

(b) It sounds like you were pretty much "all the way to the left" to me. If
she can't pass you safely, then maybe you should have been further right
(taking the lane).

Turning left at a T intersection like that, I'd position myself in the left
tire track of the lane that allows both left and right turns. If there
isn't such a lane, then I'd position myself in the right tire track of the
right-most left-turn lane. FWIW, YMMV, etc.
--
Darin McGrew, , http://www.rahul.net/mcgrew/
Web Design Group, , http://www.HTMLHelp.com/

"How long is this Beta guy going to keep testing our stuff?"