It looks like the PHZ files are just ZIP files (which I really like), however they're not compressed. As a test I created a new PHZ with compression (using Info

It looks like the PHZ files are just ZIP files (which I really like), however they're not compressed. As a test I created a new PHZ with compression (using Info-ZIP) with the contents of an existing PHZ file. I found that the compressed PHZ seems to open fine in Polar Bookshelf. What's the rationale for not using compression in PHZ files? Is there any reason for me not to update all my PHZ files to using compression?