Part of the stealth rules from Paizo:
If people are observing you using any of their senses (but typically sight), you can't use Stealth. Against most creatures, finding cover or concealment allows you to use Stealth. If your observers are momentarily distracted (such as by a Bluff check), you can attempt to use Stealth. While the others turn their attention from you, you can attempt a Stealth check if you can get to an unobserved place of some kind. This check, however, is made at a –10 penalty because you have to move fast.
Rogues can take a class talent, Fast Stealth:
Benefit: This ability allows a rogue to move at full speed using the Stealth skill without penalty.
Would fast stealth reduce or eliminate the penalty in the first case?
A related question would seem to indicate that it wouldn't, but the name of the Fast Stealth feat makes me doubtful.