This rather supports Richard's earlier assertions. The Blackmagic codec is an Uncompressed codec. The processor is not doing much work to decode this. With uncompressed video you need lots of drive bandwidth to get it off the drive, which is why RAID arrays are essential for uncompressed work.

With compressed video, it's the physical speed that the data can be accessed on the hard drives patters that's the key - not the sustained data rate. RAID does not help for this.

Photo-Jpeg performance has nothing to do with drive speed at all. Photo-Jpeg is an off-line format. It's generally used by content providers because it provides great compression ratios with a minimum loss of quality. However, it's heinously processor intensive to decode and encode - hence the shit performance.

Hugh