I would have fallen over if you told me it was at 20.
How the FSCK would you ever get that high doing the compute stuff you are doing... unless they were throwing everything at it at the same time.
I have seen machine with load averages in the 200s and greater performing just fine. It was an application server that scheduled and ran multiple, multiple, multiple servlets (or computelets) per second. It was able to keep up, but you can only execute so many a second.
In any case, these things were the cause of the 200+ load average... The CPUs, Disk I/O, Memory I/O, Memory Cache, Buffering, etc... wasn't even being pegged at 200+ Load Average. So many things to be executed and submitted at a time, some functions submitted 300 joblets (or whatever they called them) at a time.
The only time the app servers were that busy, was during Fall Registration opening and closing. Other than that, it barely rose above 2.
This was an IBM 4 Proc P9XX system doing the work with a Gaggle of Memory and nice disk perf.