The entire process is very dynamic and analysis of the end product does not necessarily tell you what went on. The problem with a student sitting down and figuring this all out is that there are multiple variables and the entire process is very non-linear; the difference between being very close and being a million mils away is not always apparent. Sometimes it does not matter how smart you are, you have to have the right recipe. That is why a number of companies have sprung up in silicon valley that offer a process for testing multiple micro-samples at once, to speed up the process of finding the right recipe. This differs substantially from a normal product development where all of the sub-components can be tested separately. A valley VC that specializes in materials based companies once told me that he never actually invests in a company that has yet to complete their materials development. This is in part, why there are so few technical glass companies in the world. A lot depends on their experience and catalog of recipes (glass chemistry, furnace chemistry, heat treating, etc.) that they have built up over time. Sometimes tramp chemical elements in the parts per billion range can have a dramatic effect on the product outcome. As semi-conductor makers are aware, softly whispering the word alkali in the fab can put enough sodium in the product to kill production. It was a parts per billion chemistry issue (with a phosphor poison) that originally put Westinghouse, the inventor of the active matrix LCD, out of the TV business.
OLED process development has exactly the same issues.