Done and very informative though the bone locking technique doesn't work for me. The locked bones still move a little when I move the parent. I have always had this problem with bones though.
I highly recommend it to everyone even if you are experienced in rigging
I just wanted to add that your English is very good and perfectly understandable. Also it was blatantly obvious to me that all answers you gave were in relation to YOUR workflow and how you like to achieve a certain result. I was enthralled from start to finish and think it was one of the best webinars so far.
Personally I've never been a big user of switch layers, but they certainly have their place. Hands, for example, could be more easily used in switch layers as hey are so complex to pose and gesture. You could also use switches to switch between complete character views, when using props perhaps... I know some people swear by switch layers when you have a lot of similar characters and already have sets of reusable groups of assets it can be better than re drawing and rigging parts for every character in your production... If you are new to AS DON'T turn your back on any feature just yet, it may save your bacon one day and by knowing every aspect youre more likely to combine skills to come up with techinques we've not yet thought of...
I've used switch layers to switch between multiple character views, each with their own skeletons. As with all these tools they all have their uses given the right occasion. Never say never