When you need to park your bike on the street temporarily (no more than few hours), if there is a bike rack area where several other bikes have been locked, is it better to lock your bike among others, or instead lock your bike alone to a signpost nearby, away from those bikes?

My concern about locking bike with other bikes is that there may be a potential thief who either is an owner of one of the bikes (cyclists would be more interested in your bike/bike parts ) or is paying close attention to the apparent bike parking area, and if he tries to steal your bike (or bike parts/accessories) it's not obvious to passersby. On the other hand, if your bike is alone some steps away, it may be a clearer target.

Thoughts?