Beck would not admit to doubts about his mormonism if he has them...the cost to him with his family and friends would be too high. Leaving the mormon church is seen as a great "sin" and taken personally by many members.
There are instances of "apostates" losing spouses, friends and family members because of it.
Also, alcoholics are prone to "magical thinking" Magical thinking: the ability to draw conclusions that are based on a persons desire for what reality should be, not necessarily upon what reality actually is.
"Magical thinking" plays well with the cognitive dissonance required to believe in Joseph Smith, visions of God and Jesus appearing to him, golden plates, the bestowing of the "keys" of the "priesthood" by Peter James and John on Joseph Smith, and the requirement of baptizing the dead as mormons by living proxies.
Beck would do well to not mention his faith on air.
This video is well done and covers the questions well ...
http://clipmarks.com/clipmark/98708079-2645-4665-92E0-A7A596AEB263/
Faith is not something to reason with, for or against.
The essence of faith is that it is *not* reasoned.