TOPIC: fiberglass strength vs age

Does anyone know if fiberglass loses strength due to age? I have been told it loses flexability after about 10 years and would be more prone to cracking if pounded too hard.I have a 1977 MFG Caprice 19 with a deep V hull, and have recently been running it in saltwater in the Gulf. Would it stand up to the pounding I see some people giving newer boats skipping over 3' waves and chop, or would I break the old girl? The stringers and floor are all original and solid, and I don't usually pound my boats unless it is an emergency like outrunning a storm. Any comments or experiences out there?