Making a spline tangent to another spline incorrectly causes the spline's direction and magnitude to become fixed.
In Figure 1 below I have two splines and a circle fixed in place on the bottom row, and 3 spines made coincident and tangent to them on the top row. On the right, the spline behaves correctly and the coincident point can be moved around the circle. In the middle, the spline behaves incorrectly. Making it tangent to the fixed spline incorrectly locks the direction and magnitude at the coincident point rather than making it change on the fly to match the tangency of the fixed spline. You can see that the coincident point incorrectly can't be moved around the fixed spline. On the right a line is first made coincident and tangent to the fixed spline, and then the spline is made coincident and tangent to the line. This behaves correctly, doesn't lock the splines direction and magnitude, and the coincident point can be moved around the spline.
Is there a setting somewhere that I'm missing or do I need to file a bug report? Given that glitches and bugs for as far back as SW 2009 are still in SW 2017... will filing a bug report really do anything? The file from the screenshot is attached below.
Figure 1. From left to right, a spline tangent to a line which is tangent to a fixed spline, a spline tangent to a fixed spline, and a spline tangent to a fixed circle
I am running: SolidWorks 2017, Windows 10, on a laptop, 8GB ram, HD Graphics 530 Graphics card, Intel Core i7-6700HQ CPU, with a know SolidWorks - graphics card incompatibility.