no - if you put the slow discs onto the HDD, they'd play as an original had been loaded onto the HDD. Basically, you have the same data on both the copy and the original, but as the dye isn't as reflective as on the original, it is slower to come off the disc as the laser has to work harder to retrieve the data. So, you won't notice any difference between putting the original or the copy on the HDD.
Basically, in short, loading your slow backup onto the HDD will cure the problems with it being slower.
