I am sure I do not know the real answer !! but I try to summarises my "feelings" .In older version ,ie squashfs-1.3 the
indexing pointer scheme was clever and allow very fast stuffs ;
but if you compress the huge_knoppix_2.2Gb then you get into trouble : that's why version 2 from Philip Lougher ! but I understand then it compresses almost in blocks "exactly as cloop"
(with probably variations ,tree structure...giving this ~5% diff)
Arranging big files at the beginning may help readout response time ,but that is related to how iso files,cdreader behave(in case of cloop) I believe you gain nothing with squashfs (we have to ask Philip at his forum).The true point I like mksquashfs is that you
are not bound to put the whole stuff in a "remastering_directory" since you can put exclude_options (I am using that way a lot)If you need response time,I believe mkztree
should be faster (however poor compression ,since block size vary a lot depending on your applications !!! remember zisofs,was included long time ago into kernel -politically correct put aside !!-)