Originally Posted by
Danhedonia
Let me add: if I were ever taking a left turn here across an intersection with traffic, there is absolutely zero chance I would ever do so without looking - nay, staring - into any and all traffic. Rely on a mirror? I'd be dead. I'm not kidding - if you've visited, you've seen our ghost bikes around town. Way, way too many.
You can safely rely on the mirror to help you
plan movements, but yeah, it's still considered wise to actually turn and look. A good double check.
Sometimes, turning and looking behind can have an undesirable effect... A driver seeing this may think you are planning to merge/turn in front of them, and then hit the brakes when you don't want them to because you were only checking... and saw a more favorable gap behind them. A head turn can be interpreted somewhat like a signal in some situations.
And seriously, I have found zero blind spots in my properly set up helmet/eyeglass mirrors. With a
slight head turn I can see it all. No place for a car to hide. Every time I do turn and look, I see nothing new.
Seeing ghost bikes can be concerning, but keep in mind that we don't really know what happened, or how the cyclist was riding or paying attention. Obviously not all cyclist behavior is the same, and some take on more risk... often without even being aware of it.