hehe,but the Intrepid has a mark 9 warpcore that allows it to achieve a speed of 9.975 impossible to for the Galaxy to reach,if you remember warp 9.6 was max speed 9.8 could destroy the ship,i highly <doubt> a ship with slower main propulsion has more power.
The Enterprise-D popped Warp 10 once. Ask Geordi. ;P
In any case, the Intrepid weighs a fraction of a typical Galaxy class starship (700,000mt versus 5,000,000, if you believe the manuals), so in terms of raw power I wouldn't think an Intrepid would NEED a powerplant with more lightbulb power than its much larger cousin.