There is a 3X Mastery event in Los Angels for the next 5 days. When the loot item was added to the inventory I thought it would be a 2X Mastery event . Zynga is either being extra generous or they want players to master Los Angels. Many have no plans or desire to do so. Staying on the lower levels of mastery makes job events and Missions a lot easier. I imagine many will continue to ignore Los Angeles. There isn't much incentive to master it as the special loot drop, (the Tenty) sucks. Below are some numbers of just how much mastery you can get per click from a random job in District 1. All jobs have different mastery percentages and this one is just an example. The extra mastery only applies to jobs and not Asset Raids. This could be a sign that Zynga want more players to hurry up and master Los Angeles already so that they can release a new destination.
Normal Mastery= 7%|VIP Mastery=8%
3X Mastery = 21%|VIP=24%
Activate the Strategist Crew Bonus = 28%|VIP=32%
Use a 2X Mastery Boost (bronze- gold only) = 35% |VIP= 40%