Originally Posted by
the Forester method, changing lanes in slow speed traffic, explaining why the Forester method instructs to not use hand signals, pg 309
Second, the traffic situation might suddenly require both hands on the handlebars and brakes....
Originally Posted by
Bekologist
with advice like this, no punches needed.
This is given as only a second reason, not the first reason, and, note, it applies to the use of the brakes. It is commonly recognized that for any but the most gentle braking, if the deceleration force has to be applied through only one hand, that forces the steering into swerving the bicycle. Therefore, in situations when braking may be suddenly required, as when cycling in traffic, it is best to have both hands on the handlebars so that the deceleration force is balanced on each side.