I don't understand how a land value tax is supposed to make rents lower. It doesn't really compute.

As a landlord, I have a mortgage of $X and taxes of $Y, and insurances, maintenance and other liabilities that total up to $Z, for operating costs on a piece of property.

For this to make any sense at all, $Rent >= $X + Y$ + $Z.

If you increase the taxes $Y (and this would, realistically, be done more or less uniformly across a town or municipal region, so all properties are going to be in the same boat), all you've done is make me have to charge a correspondingly higher rent. Rounded up to the nearest $25 or $50, because that's how it is always done. Meanwhile all the other owners of rental properties are in the same position.

Hooray!