The missing components
Contrary to what so many people may think, you don't need to have a technical answer for every possible attack, or scenario. Furthermore, such a thing is not possible because the possibilities of scenarios that might happen in reality are in fact, endless.
Instead, what you do need to have is:
1. A strong foundation in your striking, clinching, and grappling capabilities, and 2. a definite plan of action backed by the correct fighting principles of what to do and what not to do at any given attack.
Don't waste your time worrying yourself about a special technique for every type of grab or hold you could think about. Such training is purely theoretical, and would never work under the pressure of a real attack anyway. Because, if you have to think under the pressure of a real attack, chances are you already lost.
Sure, there are always some missing components, but those components don't need to exist in training, simply because there's no way of knowing exactly what might happen in the street. However, if you have a good level of striking, clinching, and grappling, and your training is based on the right principles and warrior's mentality, especially training under pressure, I guarantee you'll find the right solution for almost any scenario that might happen- because losing is never an option.
Train smart, stay safe,
ICCS head instructor