Yes they are.
Trick is to skin and debone as soon as possible.
Fried by cutting into about 3/4" strips, grilled or blackened about 3/4" steaks, very good eats.
Before the "landing in tact" regulations, I used to fillet the skin and cartilage and then put them in the cooler in a separate bag. Have since quit shark fishing when the regulations became effective.
Have been told they will excrete urine through the skin. They do look and smell like it, yellow dots all over the skin.
Oh, congratulations Wolf!