The move probably won't lead to a giant surge in sales for a luxury machine like the Model X, but it could help keep the existing sales momentum going at a time when Model 3 sales are still too new to represent a significant factor. If you can afford the Model X but found the premium over a Model S a little too hard to swallow, you might be tempted to take a second look. The gap between the 75D variants of both EVs is down to $5,000, which might be justifiable if you have kids and cargo to haul.