Tilling with geomancy bug?

[Lun]

I notice that if I attempt to till soil that's reverted to it's original state (The room will say there's 40 plots that need tilling) I till 2 plots at a time. However, if I try to go to a room without any soil it takes me 10 attempts to till in order to get 1 single plot. Is this a bug, or a feature? It seems like a bit of a... waste of energy to till using geomancy.

[Rias]

If it's a wilderness room that has never been tilled before, the initial tilling (i.e. creation of a new field) takes much longer than tilling a field that has already been established. It's intentional.