Nah... not true... in SQL Server 2005 and up, there's basically no limit to passing arrays...
http://www.sqlservercentral.com/articles/T-SQL/63003/
The author just didn't go far enough in showing how to use the EAV tables he made in his examples as a 3 dimensional array. Most people blow a couple of gears for anything above a 3 dimensional array so 3 dimensions is a good place to stop. People that need more than that will be able to figure it out quite easily.
Randal, nice job at "standing" up an array in "memory". It's a simple concept that far to many folks have forgotten and some have never learned. It's good to see it in print.
--Jeff Moden
Change is inevitable... Change for the better is not.