Lady Lucas was a very good kind of woman, not too clever to be a valuable neighbour to Mrs. Bennet. They had several children. The eldest of them, a sensible, intelligent young woman, about twenty-seven, was Elizabeth's intimate friend. (Chapter 5)

What does “not to clever to be a valuable neighbour to Mrs. Bennet” actually mean. Does it mean Lady Lucas is not tipping the intelligence scale or that she is not smart enough to make herself valuable to Mrs. Bennet. I have to say what compensation there might be in making herself valuable to Mrs. Bennet is not automatically leaping out at me. It is fun to run across a new stumper--it happens each time I reread P&P. Any thoughts? ;D