Well, the point of discussion for me is the concepts discussed herein and I've come across this mentioned before a few times already.
It is better, yes. When the system searches for data it has less data blocks to trawl through and search in order to find it or write to it. This is when read and write operations are executed. Obviously also in system wide searches, drive scans, synthetic benchmarks, database recollection, large program loadup (etc). Thus it's quicker and it preserves the HDD integrity in a more satisfactory way. You will experience better results like this, hence why Linux builds use separate partitions for page file and most Linux users will keep one partition for OS and another for data too. In fact, most corporations that I've come across make practice of the same habit. I know ours does, and it's one affiliated with the mainstream government who I know also practices the same in their hierarchical departments for better HDD/data integrity and access. Each partition can have a separate page file, which also adds a little boost.
Having separate HDDs is teh main deal though and much better as more simultaneous data can be accessed, hence why RAID striping is best for performance.
Personally, I am using this concept on my work systems and on 2 of my home ones (those with sufficient space). But mine is a little more customized; OS is HDD C, programs are HDD D, storage/documents are HDD E and backup 1 and 2 which are external USB 2.0 and FW800 drives.
But in the end, it's a something dependent on variable endless factors. It's more a matter of 'marginal' speed gains, better file integrity, better practice and organization than anything else. IDK to what extent, but enough for it to be common convention in places where it matters, hence I tend to see it as a wise move if one feels a little challenging. Nothing I would consider a need to go too deep into though.
