i agree that it is a common clearance but it is an instrument clearance and IFR rules prevail. If IMC is anticipated then one needs clearance from ATC prior to entering. The controllers assume that you are IFR qualified, IFR current in make and model. Its only if something goes wrong that the Feds will come calling and you better have the i's dotted and the t's crossed. If your VFR, then you are to remain clear of clouds at all time. When going up you are supposed to get a clearance from atc and have to read it back. Inbound you have to ask for clearance and readbck prior to entering IMC. If not ifr qualified then you should advise atc that you are unable. They are providing separation from other traffic who are anticipating a sterile pathway.