TechWhirl (TECHWR-L) is a resource for technical writing and technical communications professionals of all experience levels and in all industries to share their experiences and acquire information.
For two decades, technical communicators have turned to TechWhirl to ask and answer questions about the always-changing world of technical communications, such as tools, skills, career paths, methodologies, and emerging industries. The TechWhirl Archives and magazine, created for, by and about technical writers, offer a wealth of knowledge to everyone with an interest in any aspect of technical communications.
"...an older User Guide and have found that it uses 'the user can do this'
to describe system features, and 'you will do this' to describe specific
tasks."
Strictly speaking, this is worse than a pronoun problem; it's a shift of
voice from third to second person. The shift creates the impression that
the manual is addressed to two different people: "you" (second person) and
"the user" (third person). The reader is probably confident that s/he "will
do this," but might be waiting for someone else (the user) to perform
another function.
I know the reader can probably figure it out, but if we lean on that old
crutch, we'd just as well go home and let the engineers write this stuff.
I agree. Make it consistent, and use the second person.