Are you actually using BlobView here, or is this a DataView named blobView?  I don't like the idea of extending BlobView for writing, so if you can make this work with DataView, I think that would be best.  

But if not, and you have to add writing methods to BlobView, then it would probably be useful to put writeString() into BlobView.  Though you'd want writeASCIIString() as the name, to be clear that it isn't utf8.