A couple of months ago Adam pulled some seed out of a grow-bag and brought it into the store to shuck. The oysters had led sheltered lives... they hadn't yet been tumbled or tossed around on the beach, and so they had soft, brittle shells that broke into pieces when we shucked them. 
You might be upset if you ordered oysters in a restaurant and that mess arrived on your plate! The Hama Hama Oyster Mama was so strong in her twenties that she could twist an apple into two pieces. Now we're taking it a step further and opening oysters with our bare hands. 
It helps, of course, to have burly hands and a wimpy oyster. 
Oyster Crusher:
[…] grows quickly, its shell can become brittle. If you’ve ever shucked an oyster only to have it fall apart in your hands, you understand how disappointing a brittle shell can be. Building on centuries of oyster farming […]