I think it is worth mentioning that TCAS can be surprisingly accurate in azimuth (a wx radar return off an aircraft will often coincide with the TCAS position and tie in with the position determined by the Mark 1 eye-ball). However, NEVER, EVER use TCAS alone to manoeuvre laterally - that is not how it is designed to be used.
I think it is worth acknowleging the often high azimuth accuracy, because if people are told it is not accurate, yet see it working well every day they might consider (as Glueball suggested) using it. DO NOT!
When it comes to the RA - manoeuvre as little as possible ie just outside the red zone (whether it is on the VSI or the ADI). More separation is not necessarily better separation.
G W-H