I'm sorry you had to deal with that, JurysOut. I had one of those, as well, but he would only wait places he was sure I'd eventually wind up. (And I'm so glad this was before the internet/cell phones.)
In the scenario you're describing, how do you imagine that the person would have established that Shunick was out that night? A friend, acquaintance, random stranger? I've seen multiple confirmations of Shunick's route home, but no mention if that was the route she took to get there, especially as she was initially heading to a location other than Brettly Wilson's house.
I can see someone being stalked at the job they go to every Monday, or the class they attend every Wednesday, or anything else along those lines. But if Mickey Shunick was accosted by someone who'd seen her before on her bike route, it seems far more likely that it was a case of unfortunate chance than
it was an obsession. As always, I could be totally wrong, though.