4 principles of chess - Horrible English, valuable Chess lessons

Besides the horrible English, these might actually be the most valuable chess lessons on Youtube. It is not like in other youtubevideos that it is endless talk, and an endless presentation of moves (and I know my English is also akward). These are the insights of a grandmaster who leads you quickly to the important moments of a game. This video asks general questions about the game:

1. How long do you have for a move in a single game? (Such questions should be asked)
2. When do you think longer?
four principles
a) In the opening you should play quickly, develope pieces quickly
b) At the end of the opening you should develope a concrete plan - This means that you save time for later moves

There are some examples provided

c) Variations should be calculated in tactical positions, in strategic positions you should think generally
d) When is it time to calculate: When there is contact to the pieces of your opponent, or when you plan to make such a contact.