I think when we do a new interface we need to look at how we handle situations where the flash is much larger than the SDRAM.

It is conceivable that you would want to copy a 300 MB JFFS2 file system from a USB key to internal NAND flash in a system which only has 64-128 MB of SDRAM.

An explicit command loop to do this is IMHO too complex and error prone.

A command which copies between different storage locations is therefore desirable. (It would need intermediate SDRAM buffers)