Essential property doesn't work as expected.

Hi everybody,

Hopefully you can see the following expression on the scale property. This is how it's meant to work. Notice that the "Amount to tint" value is 75% which cause the scale of the layer to be multiplied by 0.7.

The "Amount to tint" is also an Essential Property. If used as such and set at 75% the scale gets crazy high:

This is another example with the "Amount to tint" set at 1%:

Any idea why it doesn't work? Anything wrong in the scale expression?