How can version 17 be forced to produce [VectorCalculus]TangentLine results consistent with previous versions?
Suppose you have a 3D position vector defining a curve using a parameter t. One can evaluate the curve at a specific value of t. Say the point is p. One can differentiate the curve and evaluate it at the specified value of t. Say the result is the vector v. Then the tangent line is p + tv. The VectorCalculus Tangent Line function used to return exactly that result, just like computation by hand. Now, in version 17, the TangentLine function returns a first coordinate of x and expresses the other two coordinates in terms of x. What a mess that is!!