They need to be clear what it does, Not only does it give a +5 carpentry bonus, It gives a % chance increase too like Talismens.
So even if you are GM Carpentry and don't get 105 Carpentry when you use the table, you get this:
Woodland Chest with GM Carpentry No Table - 70% Chance Normal /25 % Chance Exceptional
Woodland Chest with GM Carpentry & Table - 75% Chance Normal / 28% Chance Exceptional