Copying a disk partition, HDS reported a maximum data transfer rate of 3792kB/s (3.7MB/s) throughout the copy operation. Windows Resource Monitor by contrast reported 44MB/s!!
If the HDS figure were correct the partition copy would still be running 10 hours from now, but it just finished after about 2 hours for 250GB of data.
Hmm That's odd the Maximum Transfer rate just jumped to 59MB/s????
Definitely something strange going on here.