The access via array versus hashref would be faster, but only by a very small amount. I realize that those small amounts multiply up into larger delays, but we are talking very, very small improvements to some code that is paired up with a database query. Such small improvements do add up, but it loses the significance when paired with a database query, which is at least two orders of magnitude slower than a hash lookup, and maybe 4.
It is like packing one less T-shirt in your suitcase to save weight, when there's also a bowling ball in there.
Then again, even when it may not be necessary, optimization can be a fun pursuit, and good practice.
