Good startup mentors and bloggers still give bad advice, but it's not their fault it's ours.

The halo effect is where one's judgments of a person's character [or advice] can be influenced by one's overall impression of him or her. It can be found in a range of situations from the courtroom to the classroom. We fall prey to this when we fail to see experts advising us outside of their true experience.

Detect Halos wth ARCS:

Accomplishment: Is their advice based on direct experience?
Relevance: Is their advice extending beyond their expertise?
Constraints: Does the advice recognise what skills and resources you have?
Stage: Is the advice relevant to your stage?