Since upgrading to 2016 I have come across this issue, and I feel it is something ina  preference somewhere that has changed. Take a look at this:

Smart Dimension Issue - Kevin_Quigley's library

I am applying a vertical dimension from the hole to the base of the part (it is L shaped, the bottom sticking out towards the viewer). The vertical dimension tool gives the correct value of 50mm.

I now dow the same with the Smart Dimension tool. This time it results in 73mm.

I suspect this is something to do with the Smart Dimension tool picking up on some projected point and dimensioning in 3D space, but this has already caused me to scrap a job as I missed the error (it wasn't as obvious as this one). The thing is I have used SW since 97 and pretty much always used the Smart Dimension tool for applying dimensions on drawing sheets with no issues. In SW 2016 this tool has become unreliable due to either a bug or some preference change (which I cannot find).

Any ideas anyone?