Spiritbond Formula, Spiritbond optimizing and GC Gear?

I was scrolling through gear while leveling up some new classes and just noticed that in the GC, there's "Patriot's Choker" and "Patriot's Bracelet", which can be worn by any class and grant +1 Spiritbond each. Their iLVL is pretty low, made to be equipped by Lv30 classes.

Are these worth investing in for things like gathering of mats that don't need the stats, or mass/quicksynthing some random crafting?

Also, just in general, is there a point in which attempting to boost spiritbond just doesn't matter anymore? Using a HQ Superior Spiritbond Potion (+6), using a Squadron Spiritbond Manual (+3)... I don't even know what other spiritbond boosting options there are. With those accessories, that's a +11 to Spiritbond, which might be neat when crafting mass amounts of say, Turali Corn Oil or something else idk.