A: I imagine you are thinking from a H.R management point of view, for which I believe a good title for your dissertation may be, for example: "investigating the link between training and development strategies to organizational performance improvement". This would be a good topic for you because there is a wealth of literature on the topic, and conducting primary research for it would be straightforward.
I believe it would be essential to identify "why" organizations look to train and develop employees. A large part of this is to encourage employees to "learn". Learn about the company culture, organizational processes and new skills. Some organizations are better at this than others; for example Google is one of the leaders in encouraging employees to learn, while other companies are much more rigid in what they train employees to do.