Heat conductivity is a function of two factors, i.e. conductivity of the materials in contact and the surface area in direct contact.
1. What is the total area of the heat pipe in direct contact with meat? four square inches? How fast can you cook a turkey if your frying pan is only four square inches big?
2. The heat pipe indeed can conduct heat fast, however, speed of conductivity being a constant (assuming that the meat is not moving), how fast can meat conduct heat where is in contact with the heat pipe even the pipe can conduct heat super fast?
Also, thermal specific heat of air is extremely small for the heat pipe to collect with such a small heat collecting area.
One cubic foot of air weights 0.0807 lbs, and one lb of air has only 0.24 BTU per degree.
Just my unscientific mind trying to reason this one out.
dcarch