I admit that, comparatively, I don't know as much as Tibetan Buddhism as I should. Since this (and Shingon) are my current areas of focus, I was wondering if anyone could answer some questions for me.
1. What is the relation between Dzogchen/Mahamudra and the Six Yogas of Naropa, such as Tummo? Are these yogas part of the the Dzogchen or Mahamudra practice, how are they related?
2. Regarding the throat singing Tantric Choirs of Tibetan Buddhism, I notice that the most famous--the Gyuto--is associated with the Gelug school. Is the deep throat style mantras and choirs part of all Tibetan schools?
3. Can one begin practicing deity yoga without a teacher based on what one can learn from books and other sources? If not, why not? If so, how does one choose a particular deity/yidam? Is it simply based on what the individual is attracted to or is there a process behind such a decision?
Thanks in advance.

