I doubled HPd every summer in IAH, as did most Captains.

You can double hp and taxi all day long, just be aware of your ITT when pushing up those power levers.

-slow long taxi=good time to double HP, ITT will hold low 700s with power lever movement.

-complete stop, holding short of a runway and you just received "without delay, cross XXXX" from ATC= bad time to have that HP in.

Plus when you taxi with the double HP, you have both engines in BG which is better than just having one stalling there in ST/FX.

The people who created this rule at Colgan are the same people who never rode on a Saab in the summer and would punish a pilot if they refused to fly a plane that was too hot.