Horizontal regression: Is there a way to define maximum slew on an alignment when using a single element regression?

Hi, 

I'm doing a track off/on and to draw the alignment onto open rail using a single element regression, it appears that I need to use trial and error.

The following is my current method:

After creating a regression line using the survey, I select "single horizontal regression" and using the "horizontal curvature diagram" I create an alignment. I open up the horizontal regression report and look through it to  see if the line meets my requirements (I require the slew of the line to be less than +/- 15mm), I then edit the length and location of the alignment (via the toggle points on the curvature diagram) until the report states that it fits my requirements.

There must be a more efficient way of doing this? What is it? 

Is there a method to set the maximum slew of an alignment and then draw it?

Many thanks.