The “split” here is really an “un-connect”. The endpoints are bound together by an explicit or implicit connect. Just being close enough does not make a connection. This connected state affects certain commands like Select with Shift and ensures that Elevations flow and Trains don’t stop.
in V5.2 the default is now to connect tracks by default in Move and Rotate and in the Track Add commands. An anchor of two blue circles on the ends of the tracks one open (align target) and one filled (align source) are shown when the ends are close together regardless of angle. Releasing the mouse will cause the ends to align and connect. This can be inhibited with Shift.
i felt that the bias should be to connect rather than don’t connect. The net effect is that snapping tracks together is easier whether when adding or repositioning.