Then there is scarification - wipe a fork with rubbing alcohol, to sterilise it, then scratch the surface of the cake.

The counteracts the condition known as 'overlay' which sometimes occurs, a tough crust of mycelium that prevents pin formation.

I'll also go with Snozz on the nutrition thing. You could make a nutritious tea using horse dung or similar and inject this into the cakes using a syringe and needle (turkey baster and football pump needle at a push). Make sure everything's sterile of course!!