Originally Posted by
SalsaShark
In my experience, if the caliper arms are stiff enough to not flex in use, the seat stays will flex instead. This flex is usually a byproduct of the braking system having more than adequate power available to efficiently stop the bicycle. Linear pull brakes are quite powerful due to the high mechanical advantage of the system. I have not seen the need for compressionless housing, as it might lessen the already twitchy modulation of a bike equipped with linear pull brakes.
This being a 20" folding bike with a pair of burly, stubby stays that double both chain stays and seat stays, there is very short frame real estate between the rear wheel axle and the brake stud. That said, I could discern some barely noticeable flex near the dropouts - by a much smaller amount than that in the brake arms themselves.