Hi Marc

You will find these can both be done as they are seperate exercises with differing aims. 

The anchor finger is what you will often use in a piece of music. Along with visualising which figures will need to move and to where.

The hover technique is to develop muscle memory. Lift put down and repeat.

too early to pick and chosse your preferences.

You will develop what works for you. The beauty of an online course

Changing speed only improves with practice and is the big step forward to be able to play songs so stay with it in your practice sessions but it doesn't have to be done to the death and boredom steps in.  Repetition is needed, repetition can be boring but unavoidable. 

Dave L