Very interesting remark about the AP and pilot workload. For sure the AP is here to assist us, provided we use it correctly. Good remark from Suitecaseman regarding using the AP to hold best glide speed. In this particular case the AP was not set to assist the crew in maintaining this best glide speed. The AP basically reduced and maintained the speed well below this best glide speed, thus shortening the gliding distance and causing high Vz impact. The AP which was supposed to assist the crew basically badly deteriorated the situation and shouldn't have been kept for so long on the ILS. The aircraft was trimmed for Vref, simply disconnecting the AP would keep it flying at a more appropriate speed and extend the gliding distance. Instead of that the aircraft was maintained on a wrong glide path at cost of precious speed. The AP not only lead to reduce the gliding distance, but also Vz control.