Placement of Tape IOA Power6

Back in the 'old' days when we needed IOPs, it was best not to place a tape
controller on the same bus as a disk controller. Now the Power5 and 5+
verrsion of the 520 CPU chassis (or CEC) had at least 2 buses has does a
0595 expansion. With a little carefull planning you could separate the tape
and disk controllers on different buses. Best I can tell from the docs I've
seen the 8203-E4A CEC only has 1 bus.

So is it still important to split say a FC5904 ( large cache SAS raid
controller ) and a FC5901 ( SAS tape controller )? I can take a E4A 4core
with lots of memory and put a lot of SAS drives on that FC5904. Heck the E4A
and 36 drives across 3 EXP12s expaion only takes up 10u in a rack...