This has wind up and trap written all over it.
Certainly not intentional, so sorry if it has come across that way.
I was merely trying to say, that seeing as he is hardware limited, that he will probably never notice the difference, unless he is transferring very large files from a ramdisk or another NVM SSD. 1700 MB/s isn't exactly slow now is it. I know it is not as fast as the drive is capable of, but being limited by other components there is not a lot he can do about it without spending a shed load of cash.
I mean my self I have a Samsung 830 256GB SSD on a measly SATA 2, ( limited by my X58 board) so it only does 278MB/s but overall I never notice it being slow when copying from a a mechanical drive.