I wouldn't call it yellow "fat"; it's more like the muscle around the dorsal fin is just yellow tinged. It may cut slightly harder when filleting, but I can't tell the difference after cooking. In my experience CCs up to five pounds (the biggest I've removed from the pond yet) are still good eating.

Lots of other points to consider, though.

"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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