You may be thinking to yourself, "That is an extremely contrived example!" That's because that is an extremely contrived example. The truth is there is no good reason to use ClrList.
Using DelVar instead of ClrList allows you to save a tiny bit of memory (between 12 and 16 bytes) that ClrList doesn't delete, while keeping almost every aspect of the list clearing the same.
ClrList is (more) useful (than DelVar) when you need to set its dimension to zero but you still want to check the size of the dimension. Example:
If k=12 ClrList L1 ... If A and 2=dim(L1 Then Disp "Hello End
If you wold do the same but with DelVar instead of ClrList, you'll get an error at the second 'if'.