Everyone knows, no one cares. I can only agree for weapons. Durability loss(Which is already pretty bad) becomes horrible when using a far above current rank weapon.
It isn't just the issue of durability loss for weapons. You also will see a very noticeable drop-off in a weapon's general functionality (damage done with it, attack, and whatnot). It's much more pronounced with weapons what it does to your overall stats and abilities.
That also goes for tools. Especially
tools, actually, to the point where I'd sooner keep searching for someone to craft me something if whoever offered to do a commission for me is using a tool well beyond their rank. Proof enough if you compare a Bronze Needle and an Iron Needle and are nowhere near rank 22. However that example goes back to the issue someone mentioned of how some lower level items are, well, to put is frankly, about as fun as scrubbing a sac of hairy *expletive!*
when it comes to craft requirements, both in terms of individual pieces and where to get everything. The Hedgemole Needle needs a hedgemole spine, for example, to make the rank 12 needle.
Know what drops hedgemole spines? Hedgemoles.
Know the level of hedgemoles? In the 40s.
Anyway, SE really dropped the ball on requirements for synthesizing, to say the least. And it goes further than just the issue of optimal equipment, too; there are a lot of people who aren't able to move their lower rank wares, even if they are better for people to use, because a lot of players just want to snap up the higher ranked equipment, negative ramifications be damned. As a result, you have a more stagnant economy for new crafters who would normally be selling, say, a rank 12 plumed bronze pickaxes, because some schmoe is shouting to the high heavens in Gridania about their inventory of rank 22 iron pickaxes.
... that last example actually happened, by the way. Despite my best efforts to get people to realize this was effectively someone pulling a fast one and gimping them for a good 10 levels (he seriously would not stop shouting all day long ... ugh), people cared more about "Well, it must be better if it's higher ranked, right?" Edited, Oct 29th 2010 10:40am by ResidentLune