I think your maths is incorrect, which is probably the cause of you seeing what you're not expecting.
For example, if you run the following event every tick:
Object.Y = Object.Y + dt * 5
Then, after one second, the Object will have moved down 5 pixels (which is, I think, what you want to happen in your example).
In your equation, by multiplying dt by 1/dt (ie MonitorHz = 1/dt) then your movement becomes framerate dependent because the Object will move 5 pixels per tick.