That is debatable, because there are a number of slots where you benefit from having something, anything at all, even if it doesn't give any enchantments. That said, back slot isn't one of them.
And if you don't have any items for a slot, creating something to fill it does mean you get maximum use out of it: better there then some other, hotly contested slot.
You are referring to the hat and pants slot which give damage reduction via Power? shield slot base damage reduction, and weapon slot base damage?
as you said, back slot is not such a slot. And I was talking about items with enchantment. Also, to be honest if someone was trying to maximize those things they would have done so.
If we are talking enchantment, a decent amount of items have a tradeoff that might not be suited for you at that very moment... actually this very example is exactly of one such item. The Carpe back slot item that increases combat frequency, this is sometimes useful in some quests, but usually harmful in most quests where you want to increase noncombats instead
Also, we are talking specifically about creating, which costs resources (for example, your 1/day floundry use). And specifically creating to fill space rather than to fulfil the actual maximization string. Creating to fulfill the specific maximization request being made is reasonable, creating stuff that does not even do anything for the maximization request just to fill slots is burning resources that are best conserved for other things.