Easiest way to send multiple iWork attachments as Office documents
The sending of windows friendly attachments doesn't change the file, but it changes how Apple encodes the files into text for transmission. (think using tar and gzip instead of uuencode and compress).

If you send many documents in Word format, there's nothing preventing you from storing them all to the filesystem as .doc (or .docx) and letting pages import them when she edits. That way she does the conversion only when she needs to modify a file as opposed to having to do the conversion at send time.