Teardown 15 - The Speed Deal (All Objectives)

I promise I didn't cheat when setting this one up, at least from the point of watching how somebody else beat a tricky time challenge that seemed impossible legitimately. I did attempt it legitimately several times, and when I got frustrated and destroyed a gate out of frustration, I realized unintentionally that the gates themselves could be moved if you didn't break the tower in the grass. I have a good feeling the devs intended this, especially if this "trick" has been in the game this long past release given other tricks that have been patched out.