Caliban: That's an awesome rule! I think we could use that.
Assuming good ole' Bocata was going to make his armor magical anyway, he could make it for size a Medium creature and it will resize itself to fit him. Unless Skip decided that armor won't resize itself up or down size categories. But according to DMG, magical armor resizes itself to the wearer so
Or how about: your skill check * # you beat the DC by (minimum 1) = amount done per week in GP.
So if Bocata took 10 on his check (result of 52), he would beat the DC of 18 by 34. 52 x 34 = 1,768 gp/wk. So he's done with average full plate in less than a week.
He beats the DC of 20 by 32 so that's 1,664 gp/wk.
9,000/1,664 = 5.4 weeks for a suit of medium mithral full plate armor, about 12 weeks (3 months), for a set of Large of the same. Considering he could sell that bad boy for 10,500, and paid 1/3 for materials, that's a profit of 7,000gp for 5-6 weeks of work if he sells it as-is. Pay a few bills and he still lives very well.
Example 2:
My 4th level archer has (7 ranks + 3 mod = ) +10 to his Craft:Bowmaking and uses masterwork tools. So he'll take 10 on his check and get 22 for the masterwork component of his longbow.
So he'd get 40 gp per week done toward his masterwork component and would finish it in 7.5 weeks.
Using the regular method, he'll finish in 6.8 weeks.
So what we see is that the learning curve with my method is much slower than the PHB method, but pays off greatly at high levels. Throw in tongs of the armorer from Magic of Faerun to get +10 to your check and it goes much faster.