PDF vs. Hard Copy

[Thomas Quine <thomas -dot- quine -at- NCOMPASSLABS -dot- COM>]

Does anyone have hard evidence (opinions are not going to help me much
here...) on the efficiency of PDF-based documentation? I'm especially
interested in user surveys or usability studies.
I'm new to this list, so apologies for returning to what must be a very old
bone of contention you all thought (hoped?) would have been deeply buried
by now.
My new employer intends to ship almost all user documentation (10 pieces)
in PDF format for our next release. The files will reside on the CD-ROM
with the product, and on our Web site.
I see PDF as a portable document format, which allows you to maintain
visual integrity in a document intended to be printed. It is not
well-suited to online help or online documentation.
This means we are asking the user to print out the documentation. Of
course, we are including a hard copy of the Installation Guide.
My experience has always been that the moment you introduce an obstacle
between the user and the documentation, you lose a percentage of them. The
obstacle here is that our customer (Fortune 1000 companies) will have to
print, punch, and bind ten documents for every user of our multi-user
product.
My fear is that the manuals my department has worked so hard to create will
be read by only a small portion of their intended audience. This will
obviously be a hit on the product's usability.
Tell me I'm wrong!
Has anyone out there done or come across a serious study of the issue,
backed up by user surveys or usability studies?
Has anyone had real-life experience (good or bad) using PDF-based
documentation? Any feedback from real users you could share?
Thanks in advance,

Thom Quine
Technical Documentation Manager
NCompass Labs, Inc.
Vancouver, B. C.
Canada

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