Should you utilise the church spy?

During my ministry career I switched churches on three occasions. 
Over the last two decades I've seen around a dozen ministry agents come and go - both as a congregation member and as the only other staff member.

In ministry, people transition.
Additionally, in ministry, people know many others within churches.

My pondering is about church spies. 
Should you use them?

Should a prospective or incoming minister "get the goss" on the new church or secure the "inside word" on where they are going?
Should they, like I did at times, chat to the outgoing ministry agent?
Should they, innocently or not, connect with a member of the congregation?
Should they check the responses the interview panel gave with the real "lay of the land?"

As a professional, it makes perfect sense to go in with as much information as possible.

But, do you threaten to poison the well before you arrive?
Do you expose yourself to unhelpful, or even untrue, preconceived ideas?
Shouldn't those in a new church deserve, more or less, a clean slate with an incoming minister?

Frankly, I rathered going into a place with my eyes open.

But, interacting with someone - be it the church council chair, treasures, secretary, lay leader, church gatekeeper, or ill-regular attendee - might work better if you don't go in wearing the lenses of your church mole.