HDCD into Upsampling DAC?? Possible??

I own two CD players that I love dearly. My main unit is a Cambridge Audio Azur 740C; I think the best-sounding sub-$2000 player I've ever heard. Although I don't completely understand "upsampling", the 740C clearly brings out air and depth to all Redbook and most audiophile CDs. My second player is my faithful Arcam Alpha 8SE HDCD player. The Arcam is clearly inferior with most discs, but some of the better audiophile-grade HDCDs seem to have more "bloom" through the Arcam. As the 740C has digital inputs for use as a stand-alone DAC, would it make any sense to run the Arcam's digital out through the 740's upsampling DACs?? Would the Pacific Microsonics HDCD layer pass through and somehow enhance the already upsampled 24-bit 384khz output? Just a wild hair... Thanks.