Points, also known as 'nodes' or 'joints', are automatically added at the I (start) and J (end) points of pipe, component, and frame elements. A tee component is different in that it has 3 end points and an internal point at the tee centerpoint.
If a point or pipe support is drawn or inserted along the length of an existing pipe, frame, or component, those elements will be properly meshed for internal analysis, but the pipe or frame element will keep its original length. This functionality has the benefit of enabling users to move/slide point and support locations using Edit>Move or Edit>Slide commands without having to manually divide the piping or frame elements.
...