The 290 vs 300 thing is irrelevant, theres a lot more to an engine than just what happens at peak rpm under full throttle, heres an example:
Car is a 2011 Audi A4 2.0 TSi 211hp quattro. It is mapped on the dyno and makes very nice figures, but there are 2 maps that looked like ignition advance at part throttle which the dyno cant measure to an extent as they are only low throttle, low load based maps that play a part whilst pulling out of junctions or cruising.
Car is mapped, customer is happy after a test drive, goes really well on the road. Customer drops in the next day to give us feedback and asks if we can give it a bit more at light throttle, not wanting to touch the boost at these areas of the map I play with the load maps and the 2 ignition advance maps, do a bit of logging and return the car.
Customer returns after 10-15 mins and is blown away by the difference, so much so that he makes me drive it. I am amazed by the difference, It feels like 500kg has been removed from the car due to the low throttle response and the way the car drives and gets up to speed with very little throttle input. Instantly the car feels as if its gained loads of power, but on the dyno it will not make the slightest bit of difference to the torque curve or power output.
A good map isnt about high numbers at high RPM under full throttle, its about the driving experience as a whole. We see maps made by some tuners that are just a simple percentage change to the throttle map to make the car feel fast, others that only alter the boost/torque limiters/ign advance/fuel when the car is under 100% load. Think of an ECU map as a dynamic 4d object, not a 2d dyno plot.
