First good when you deal with pgpnetshare.exe
http://www.symantec.com/business/support/index?page=content&id=DOC6312
Regarding only encrypt "missing" files:
--verifiy with an added encrypt command might be usefull.
You are correct that --reencrypt-delta touches all files but it only changes the metadata (around 4kb per file at Max usually smaller).
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By default, --reencrypt-delta does not re-encrypt the already encrypted data; it re-encrypts the metadata. You can force it to re-encrypt the data using --reencrypt-full as an option.
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