considerations.md: use clearer links to describe concepts

Signed-off-by: Erik Hollensbe <github@hollensbe.org>

considerations.md

@@ -5,7 +5,7 @@ Instead they MUST ignore unknown properties.
 
 # Canonicalization
 
-OCI Images [are](descriptor.md) [content-addressable](image-layout.md).
+All of the constituent components of the OCI Image specification are content-addressable; for more background on this, see the [descriptor](descriptor.md) documentation.
 One benefit of content-addressable storage is easy deduplication.
 Many images might depend on a particular [layer](layer.md), but there will only be one blob in the [store](image-layout.md).
 With a different serialization, that same semantic layer would have a different hash, and if both versions of the layer are referenced there will be two blobs with the same semantic content.