I will concede that the SDN does act in the same way as the e-notice would; however, strictly speaking, the info notice does state that it cannot be used when a signature is required and, as such, I will not accept the SDN for any signature required package(s) regardless of shipper. The only exception would be if the consignee requested an indirect to a neighbor.
This will be my last comment on this topic---if we are allowed to accept a SDN for apple shipments why was it stressed repeatedly during our training that we are to compare 1Z's on the e-notice(s) with those on the package(s)? This cannot be done with a SDN.