Striping and splitting

[aj]

SQL Server 2005 SP2

I read the excellent advice
"Optimize tempdb in SQL Server by striping and splitting to multiple
files" at
http://searchsqlserver.techtarget.co...276989,00.html

My question: All of my database files, primary and log, are on a SAN
that is using RAID 10 -- so these files are striped and mirrored across
multiple spindles anyway.

Will I get any advantage from creating multiple files per processor in
my filegroups, as the article suggests?

Will SQL Server be smart enough to use multiple workers (threads?) with
a single file, or do I have to signal that it should do that by creating
multiple files in my filegroups?

TIA

aj