Phil, Most guns finished in the 20th century did not have the "hidden" wood even sealed. This is true of the L.C. Smith products. Sidelocks by their nature/design have more wood removed than do boxlocks. Hence they are more "fragile" and sensitive to the ravages of oil and cleaning chemicals that seep into the head of the stock. Rev. Dr. Drew's quote is excellent and correct. Once the cracks appear at the apex of the locks, you can just about bet the farm that there are more serious defects lurking beneath the locks and behind the top lever through bolt. It is not an insurmountable problem but needs attention by someone who truly cares about our gracious, but aging, "Sweet Elsies". Best, Dr. BILL