Both TalkTalk and BT have agreed to change their processes following the mystery shopper tests.

BBC: BT trialist

If loose lips sink ships, a too-revealing mystery shopper could certainly submerge an hotelier or two.

CNN: Confessions of a hotel mystery shopper

Mystery shopper tests conducted by Ofcom have revealed that UK providers are failing to inform customers about broadband speeds.

BBC: BT trialist

But a mystery shopper exercise carried out by 5 live Investigates found that some letting agents were still charging fees.

BBC: Call to clamp down on unscrupulous letting agents

But like a CIA agent or the rare hair stylist who'll keep your secrets, gossip is not in the mystery shopper's after-hours repertoire.

CNN: Confessions of a hotel mystery shopper

The catch: we would speak by phone, with Goldstein playing watchdog, and the mystery shopper would remain nameless and description-less -- more incognito than Brangelina on holiday.

CNN: Confessions of a hotel mystery shopper

Cantalupo took Roberts' mystery-shopper idea--which many operators thought was designed to punish them--and made the data more operator-friendly.

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