Back in the early days of Everquest, I 3 boxed using a program called WinEQ (created by Lax). Many times during those years the question was asked if installing EQ on multiple drives/folders would increase performance. The general consensus back then was no. In fact, the question was raised so many times that Lax added it to the WinEQ2 FAQ:

"Q: Should I use the same folder for each session of my game, or separate folders?
Short answer: Same folder
Long answer: It is a common myth that game performance can be increased by using mulitple folders, possibly even on separate
hard drives. The thinking goes that using separate copies of the files will allow them to be used independently and hopefully faster than
trying to use the same files. However, this is not the case. A relatively simple concept in computer science says that hard drive
accesses are slow, and memory accesses are fast -- about 10 milliseconds for hard drive access, and under 100 nanoseconds for
memory access (as low as about 5ns depending on if the memory is stored on the CPU or if it is system RAM, etc), a ratio of 10 to 10,000,000.
That's a pretty big difference. The point of explaining this is modern computer systems employ several "cache" systems to reduce the amount of
file accesses as well as file access times by reusing unchanged data directly from memory, or by predicting the next data to be retrieved
(for an easy to understand example, if you read the first half of a file, you can be expected to also read the second half). By using a
separate folder, these cache systems cannot recognize that the data being read is actually the same. This means that instead of 10,000,010
nanoseconds for loading time for two sessions, it will probably be 20,000,000 nanoseconds because the entire data must be read twice. In
terms of loading time, you have absolutely nothing to lose by using a single folder on a single hard drive, and can reasonably expect it to
be faster than using multiple folders, regardless of whether it is on another physical hard drive. Note that it may be possible in some cases
to see performance increases by using a separate hard drive, but the hard drives MUST be on a separate IDE channel, or they are competing
for the same resources anyway (or use SATA, etc), and it is still unlikely that this will show improvement over a single folder."

Source: http://www.lavishsoft.com/wiki/index.php/WinEQ2:FAQ


This explanation seemed to make sense back then and I have considered it general computing knowledge until now. Nowadays I am reading all over this forum about multi-folder installs/symlinking and it got me wondering. I know that things change considerably in the computing world and that EQ was a long time ago but I still wonder, has the advances in hardware and operating systems made this advice obsolete?