Kundalini is just raw power, the energy of creation; this is an inconceivable amount of energy. It would annihilate you within a second without the modulating impulse of the guru principle.
The guru is like a transformer, taking the raw, unbounded energy of creation and modifying it into a flow of energy that is conditioned and useful to you as a life form. Instead of destroying you, this energy awakens you, it illuminates you, causing your spirit to unfold.
This is the shaktipat impulse and it carries within it the compression of time and space. Tens of thousands of incarnations are compressed into the space of one lifetime, making it possible for you to undergo huge evolutionary leaps within a single incarnation.