I had some extra paint left over on my palette so I decided to do a quick 2hr master study from Bouguereau. I learned two things while working on this:
1. It's better to start with accurate values in the ebauche instead of toning up or down. I often times start an oil painting with darker tones and then work up, but it's better to adjust tones based on accurate values right off the bat.
2. Use large brushes. It's always better to go for large planes and work in the detail later.