[UncleBob]

as far as "power under the curve" they are refering to, to put it simply, the average hp through the RPM. IE, peak power isn't as important as having the most broad power possible.

It really depends what application is being applied. Some forms of performance, peak power is more worthwhile than broad power. What tranny you use, for example, can change what is more desirable also.

Dyno's in general, is measuring HP (and torque if setup for it) at the tires, most commonly, adjusted for all possible variables such as altitude, temp, humidity, etc. Thats the theory anyway. There is a lot of variables, one of the biggest being the manufacturer of the dyno. Dyno readings can vary a lot between them.

The main point of dyno's is to be a tuning tool. That being, being familiar with a particular dyno, understanding its possible limitations, and doing before/after readings to verify peak performance, and/or tuning a particular setup using the results of the dyno runs.

The other side of dyno's is the bragging rights. Which is, the biggest number wins, regardless to its truthfulness. This is a fuzzy area, and I think is the bigger issue with dyno's. The shop that has a "optimistic" dyno gets more business for this reason. People prefer bragging rights over real results.