This is a strategy I've been using pretty often lately in order to get around the fact that whispers are announced, but I haven't seen many others using it. The premise of the strategy is that if you want to share information with someone, you whisper them along with 2-3 others. You send the others irrelevant messages while sending your intended message to the person you want to whisper. For example if you're Witch and find a Mafia member, you can use that strategy to hide the fact that you're trying to connect with the Mafia, and people will likely assume that you're just sending random whispers to all your targets. I've also used it to share info with other Mafia members during the day and to create TP chains. It's especially useful as Mafia since people can't really use your whisper history to backroad the other Mafia after you die.
The main downside is that it takes 3-4x as much time to send extra whispers that you could spend trying to find scum or trying to cause a mislynch depending on your alignment. And some people may see it as spamming, but as long as you keep it to 4 people max and don't do it too often it shouldn't be an issue.