Missing words in 3.1.2

3.1.2 currently reads "*3.1.2 Configurable Default Rendering: *The user 
has a global option to specify which types of alternative content by 
default and, in cases where the alternative content has different 
dimensions than the original content, how the layout/reflow of the 
document should be handled. (Level A)"

It's obviously missing some words in "specify which types of alternative 
content by default", which should probably read something like  "specify 
which types of alternative content /to render /by default".

However, I'm not sure whether 3.1.2 should explicitly address whether 
the alternative content must /replace /the regular content, or whether 
it's also acceptable for the user agent to supplement the regular 
content with the alternative content (e.g. show alt text in brackets 
after or beneath an image).

     Thanks,
     Greg