Why would it be? You use them to map a boost cure to how you want the boost to be. Wether you want it to spike at 40 psi then drop to 34 held or hit 30 and hold it and tail off to 28 higher up. You use your ECU to work the injector how you want it to work.

Did you read the link Moonie posted? If not, I would do as it tells you all about them.