In a private game with 3 friends, 2 of us have a tycoon. From what I understand, they reduce the time it takes to produce new drillers by 50%, but they only bring the timer down to 5.3 hours rather than 4, 50% of the usual 8.
No that is correct. It doesn't reduce the time it takes to produce drillers by half or 50%, it INCREASES the speed of the mine by 50%. So it's producing drillers at 150% speed. If you had another tycoon it would add another 50% on top of that and you'd be producing drillers at 200% speed or twice as fast as normal. Thus, 4 instead of 8 hours. 5.3 is 2.65 hours or 1/3rd quicker, because 50% of 150% speed is one third. Hope this helps.