If the legislative intent would have been to ONLY prohibit such movement from "within" the intersection, it would have been much easier for them and much clearer for us, had they used word "within" the intersection instead of "at" the intersection. Don't you think?
Furthermore, 22101 clearly applies to the presence of the vehicle is "a clearly marked traffic lane provided for the approach to the turning movement" and any movement that is not in compliance with the directions of or is contrary to that which is allowed by traffic control devices thereon is unlawful. That lane, and the markings thereon, starts at the entry point to the lane, and ends at the limit line for the intersection. Even if you were to argue that the lane starts at its entry point, and ends on the other side of the intersection, the same VC would still prohibit any movement other than that allowed by the traffic control devices from the ENTIRE LANE, not only that which is made from "within" the intersection.
Of course, you are free to argue otherwise!
And nowhere does it say "within" the intersection.
Again, the code references a "clearly marked traffic lane is provided for the approach to the turning movement" where the markings (any or all of the following: the straight white line, the left turn arrow painted on the pavement, the Left Turn Arrow posted on the sign, the Left Turn Arrow on the traffic light) conform to the definition of an "official traffic control device" (see below) and any turning movement not in compliance with the direction of those devices is unlawful.
Also, please note that it also states "the approach to the turning movement"... Are you saying that the "approach to the turning movement" can be made from "within" the intersection?
CVC 22101
For the Xth time (I stopped counting a while back), 22101 clearly states that if there is a clearly marked lane dedicated for a particular movement, any other movement made from that same lane is unlawful. In other words, and as I sataed in the quote you cited "once you've entered such a lane, you have committed to making the left turn"...
If you say so....
True... But the sign you described is only ONE METHOD of prohibiting such action.
Where in 22101 does it say that the alleged act committed by the OP is ONLY prohibited IF AND ONLY IF there exists a sign that stated "This lane MUST turn left". It doesn't. 22101 prohibits any movement from that lane except for the movement indicated by way of an "official traffic control device" which includes but IS NOT LIMITED TO a posted sign that only allows that movement.
VC 440. An "official traffic control device" is any sign, signal, marking, or device, consistent with Section 21400, placed or erected by authority of a public body or official having jurisdiction, for the purpose of regulating, warning, or guiding traffic, but does not include islands, curbs, traffic barriers, speed humps, speed bumps, or other roadway design features.
A "sign" could be a "Left Lane MUST Turn left", but it could simply mean a "left turn arrow" posted either at the near side of the intersection or atop the traffic light on the far end of the intersection.
A "signal" could be that "Red Light Arrow" (which I can only assume that it was erected at the intersection).
VC 445. An "official traffic control signal" is any device, whether manually, electrically or mechanically operated, by which traffic is alternately directed to stop and proceed and which is erected by authority of a public body or official having jurisdiction.
A "marking" could be a "left turn arrow" or the words "Left Turn Only" painted on the pavement within that particular lane.
It is my opinion, that the only lawful way to leave the LEFT TURN LANE is by making a LEFT TURN. So does it really matter where or when he left the lane?
Try it and see how it works... Just keep in mind that your strongest defense against any violation of any vehicle code section (or any charge for that matter), is to attempt to convince the court that the elements of the offense with which you were charged did not occur. In this case, stating that you were in a lane that is clearly marked for a left turn, and yet you opted to disregard the direction of an official traffic control device(s) (likely more than one device) that only allows a LEFT TURN, by exiting that lane, (because you think that "'at' the intersection" should mean "'within' the intersection), is in and of itself an admission of guilt (albeit indirectly) to a violation of 22101(d). So much for proving, beyond a reasonable doubt that the element of the offense did not occur.
See? This is pretty typical of what happens in traffic court... Defendant goes up before the judge, either directly or indirectly admits to committing the violation, loses the case and then blames it on "lying cops" and/or so called "kangaroo courts".![]()

If for some reason you don't like my posts simply because you disagreed with my opinion(s), you're free to scroll past them... 
