[saml-dev] Question about TARGET

Question about:
        cs-sstc-bindings-00



In Browser/POST Profile, the TARGET is trasfered in step 1,2 and 3 is for
checking with samlp:Recipient for Contermeasure MITM Attack  (4.1.2.7.2),

but

Why is transfered TARGET in step 1,2 and 3 in  Browser/Artifact Profile of
SAML ???