what you say in (1) is true (but there are ways to pull things apart, but it can be fragile, look what IE12 claims it is now !!)

But (2) is more to the point. I am trying to get BinaryBlob support working again in IE11 and IE12, The issue with the old code was that IE does not support FileReader.readAsBinaryString (see https://developer.mozilla.org/en-US/docs/Web/API/FileReader.readAsBinaryString)

So I am using the new typed array reader which seems to have more cross browser support (and is the ONLY way in IE11 and IE12) 

readAsArrayBuffer method (see
http://msdn.microsoft.com/en-us/library/ie/hh772312(v=vs.85).aspx )