Browsing through the people LinkedIn recommends I should link to, people it thinks I may know, I just discovered that LinkedIn not only flags what people I may enjoy contacting, but it often clearly flags what people to avoid.
There are a small number of people around that I’ve had a very bad experience with. Anyone that recommends any of these guys or is recommended by them, is automatically very suspect to me. One explanation for the recommendation is that they’re similar in character (a bad sign). Another is naivité (not a much better sign).
In other words, LinkedIn may be a valuable tool to filter out people you should avoid and not waste time on. Maybe even more so than the other way around. When someone you know and trust links to someone you know and mistrust, it has a tendency to diminish the trusted person more than it enhances the mistrusted person. Especially recommendations have this effect. Simple links may not mean that much.
So, be careful who you link to, and especially who you recommend. Or who you accept recommendations from (you can decline, you know). It may reflect badly on you.