This works great if you play caelum. Their starting army can patrol and tax at 170% without any unrest. If you buy 3 mammoths and a level 2 priest (to cast sermon of courage of course)on turn 1, on turn 2 you can expand with the mammoths while leaving the home army on patrol. Turn 2 you can recruit 3 more mammoths and another level 2 priest.
Most other starting armies can do anywhere from 130%(Ulm) to 150% (Monkey nations, T'ien Chi) without causing unrest.
If you take order, I think the couple hundred peasents killed are worth the extra gold. Faster expansion and the early second fort is worth it, definitely, in most cases.