Because the structure of an oil painting is inherently complex, it’s always best to attempt keep both it and its various components as simple as possible. However, this element of simplicity should not necessarily extend to purchasing ready-made materials if the hope or expectation is to create higher quality work: generic materials have a strong tendency to produce generic work. While boutique materials are usually higher quality, this is not necessarily the case with the oil. And they still don’t impart the vital information about the nuts and bolts of the craft: at the end of the day, there is no real process, just a set of purchases, a pseudo-craft.

Go read the whole thing.

Painters such as Velazquez and Rembrandt routinely added such materials to their paint. Tad seems well on his way to recreating some of their methods.

Aside from this, Tad has lots of great info on oil painting, including a well-written and useful introduction for beginners. Go there now.