I ran across something rather strange yesterday. I was trying to use Object Snap Tracking to infer a distance of 5" to the left of an inside corner of a polyline to create a line in a specific place. However, each time I tried, the line started in the wrong place. It wasn't until I tried entering "non" and then 5" did I find that it was something in my OSNAP settings causing the issue.

I went through each option one-by-one until I found the culprit. It was "Nearest". I have found that I like to have nearest enabled, but OST simply doesn't work the way I believe it should when it is.

Here's how to recreate the issue (make sure nearest is selected and object snap & object snap tracking are enabled):

1. Create a polyline in the shape of a rectangle, 5' x 5' and close the object when creating the last line

2. Offset that rectangle by 1' inside the original shape (you should now have a 1' smaller rectangle inside the 5' rectangle)

3. Draw an arbitrary line somewhere off to the side by clicking the first and second point

4. Undo the creation of that arbitrary line by pressing CMD-Z

5. Try to create a new line but instead of clicking the first point, hover over the bottom right corner of the smaller rectangle (the one inside the larger one) to infer to the left (the green dashes) and type in 5"

You should see that the basepoint of your new line is not 5" to the left of that bottom corner, but 5" away from the second point of the abirtrary line you drew in step 3. Turn off nearest from your OSNAP settings and it works perfectly.

It took me a few hours to figure out what was going on and how to get around the issue, but after discussions with a few other people, no one can figure out why it's working like this. Is it a bug? Is there an explanation that makes sense?

Thanks in advance for any help!