Not so :happyyes:. You can't put the tracing signal into a single pair since it doesn't radiate much at all. I use a cut off net cable with all the whites twisted together, clip the toner to that and usually let the toner's other lead float. Even floating, the signal is usually easy to find. If not, ground the off side of the toner and watch out, that's a hot signal.Oh, to answer your question about probes and toners- CAT5 and 6 is notoriously difficult to trace because of the tight twists so you need a high output tone generator and a sensitive probe.
Just like tracing coax- put the toner on the shield, not on the center.