Comment by jnordwick

You are forgetting about the function prologue, epilogue, and the maintenance of the various pointers. It certainly isn't as simple as a jump as you imply. To do proper TCO most implementation resort to function trampolines and other self-modifying trickery to get similar to loop-like performance. Within the confines of the JVM, without doing extensive source analysis, I doubt there is even a way to do it.