Rules question: Stealth and Move Silently

[Dren Nas]

Do the 1/2 speed reductions stack(making it quarter speed), or does one-half normal speed cover both skill checks?

[nedz]

You can move up to one-half your normal speed and hide at no penalty. When moving at a speed greater than one-half but less than your normal speed, you take a -5 penalty.

You can move up to one-half your normal speed at no penalty. When moving at a speed greater than one-half but less than your full speed, you take a -5 penalty.
There is no indication that they stack so moving at half speed is sufficient to get the full bonus for both.