I found the discrepency in the Gargoyle cloth items...
Unlike every other Tailor item (that start at 50% to make at the base skill), Gargoyle Cloth items start at 0% (just like smith items).
Therefore, to get into the 60% to 80% sweet spot, you have to be 30 points higher than the base skill to start making the items.
Gargoyle kilts: 82.9 base. Enters the "sweet spot" at 112.9. Top of sweet spot range is over 120 for all Gargoyle cloth items.
Gargoyle Arms: 87.1 base. Enters the sweet spot" at 117.9.
Gargoyle legs and chest types have their sweet spot range starting at over 120.
So, pretty much, the rule is now to switch to Gargoyle kilts at 109 or so (near the end of the oil cloth range with a 120 PS used), and stay on them until the end of training, if you plan to recycle items at the end of each crafting session (making Make max and salvage bags indespensable).
If you want to make items for Britain Library turn-in points, you make cloth ninja hoods until 115, and turn them in, then go to the Kilts (and recycling).