I have been the owner of a 32" barreled 16 ga. L C Smith for some 15+ years. When I got it the wood was perfect, in all respects, not oil soaked in the least. I used it only for doves with 1 oz. loads and never had an issue. I used it on a crow shoot one time with 1 1/8 oz. loads where I shot maybe one and one-half boxes of shells. After that I noticed tiny hairline cracks developing behind the lock plates, both sides. I had it addressed by Jim Kelly of Darlington Gun Works and stopped the damage.
I do understand that L C Smiths are more prone to this cracking than boxlocks but I really believe it might have never occurred had I stayed with 1 oz. or lighter loads. IMHO if you want to use 1 1/8 oz. or heavier payloads in vintage doubles go up a gauge to the 12.
