Why is Yamaha playing hardball with Jorge Lorenzo?

This week, Ducati revealed that Yamaha has refused to give Lorenzo permission to participate in a second Ducati test before his contract with Yamaha ends on Dec. 31. Lorenzo will be able to get his first ride on the Ducati in the test that follows the season-ending round in Valencia. But Ducati had planned another test later that month in Jerez, and Yamaha refused to release Lorenzo for the second test.

In 2010, Yamaha released Valentino Rossi to test the Ducati (the test where he famously realized he'd made a terrible mistake by switching), though there was just one test between the end of the season and the end of the year, rather than two, in this case. Suzuki has released Lorenzo's replacement, Maverick Viñales, to test for Yamaha both at Valencia and later at Sepang in November. Ducati released Andrea Iannone to test at Suzuki, where he replaces Viñales.

So why is Yamaha deviating from the usual sportsmanship and cracking down on Lorenzo? Theories are multiplying on social media, but the ones that are remotely plausible fit two general categories: Lorenzo did something that really ticked off Yamaha, or Yamaha is really worried about how fast he'll be next year on a Ducati and they want to deny the Ducati team as much information as possible.

What's your theory?