In the Fat over Lean principle, how should layers be built?

• A. Use leaner layers above fatter layers
• B. Do not apply multiple layers
• C. Build increasingly flexible layers on top of each other
• D. Always finish with oil on top

Answer: (C)

Fat over Lean means layers should become more flexible as you build them. Lean layers dry faster and contract more as they cure, so you start with these to form a stable base. Then you add layers with increasing oil content on top, so each successive layer is more flexible than the one beneath. This keeps the upper layers from cracking as the lower layers dry and move. So the best choice describes building increasingly flexible layers on top of each other. The other options misstate the layering order, suggest skipping layers, or overstate finishing with oil on top.