This can cause the jerkiness you described, as it is allowing the engine to rev up before the car is ready to accelerate in the desired gear. (mechanics.stackexchange.com)
Even if you did, you can shift to your desired gear by moving the shifter in the same direction as you previously did. (mechanics.stackexchange.com)
The fork moves the collar to the desired gear, and dog teeth on the collar mesh up with holes on the gear in order to engage it. (auto.howstuffworks.com)