A manufacturers conversion course is not designed to teach you to fly. It is only to show you how to operate the equipment. The being able to fly part is taken as already known. They provide books and procedures to allow the pilot to familiarise himself with systems etc.
In the past this worked well. To get onto complex aircraft a pilot had to learn his craft on something more basic. And when experienced was hired onto heavy metal. Now, the majority of pilots attend a sausage factory of basic training. Conduct CBT and legal minimum SIM and line training, and start their careers on a 737 or 320. They never had a chance to learn how to fly. Most have never had a person teach them systems, only a CBT.
Now these fellas are Captains and training Captains .