HEY KIDS? WANT SOME COOL TIPS AND TRICKS? CHECK THIS OUT!
If the daycare still works like it used to, this might be a good power-leveling trick. I'll test it out now.
edit: It works. Maybe I'll write a calculator to show how much time would be required to level up different pokemon to certain levels.
edit2: Lv 1 to Lv 40 took an hour on a Charmander.