Wearing a civilian motorcycle jacket over a turtle is wrong and here's why:
quite uncomfortable to remove/put on "turtle" every time
the majority of the "turtle" dedicated to the city and is poorly protected from abrasion, thin grid on which are mounted all of the protective parts will break in the first place and the skin do not protect, motorcycle jackets keep much more long-lasting friction
in the so-called "turtles" protective elements are made of plastic, plastic is much worse absorbs shock force in contrast to the material D3O, which is used in all motorcycle jackets Icon
"turtle" is used mainly when driving off-road, for the city it is better to use a motorcycle jacket