We have these here already. It works the same as other signs. The solid red means stop. The solid yellow is same as normal. Solid green means go. The only difference is the flashing yellow, which doesn't change meaning either. Flashing yellow has always been used as a yield.
We also have lights with both a green "dot" and a green "arrow." When only the green dot is illuminated, it means an unprotected left turn is allowed. When both the green dot and green arrow is present, the left turn is protected. The above signal with the flashing yellow means the same thing and in my mind is clearer as to its meaning. I absolutely hate the use of the green dot for an unprotected left turn. The shape of the signal is not clear in meaning. Changes in color or flashing vs. steady, have much more meaning. The flashing yellow is also consistent. Flashing yellow, regardless of shape, always means yield. Flashing red, replaces a stop sign. Solid red means stop and stay stopped. Solid green always means go.
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Cat 2 Track, Cat 3 Road.
"If you’re new enough [to racing] that you would ask such question, then i would hazard a guess that if you just made up a workout that sounded hard to do, and did it, you’d probably get faster." --
the tiniest sprinter