Deflationary currency discourages spending, increases the value of debt, causes people to hoard cash, and potentially causes wage unemployment.
(I don't intend that as a rhetorical question - I'm sincerely asking.)
Curious, are US treasuries or interest in a savings account considered "dead weight" in your definition?
[1] http://treasurydirect.gov/NP/debt/current [2] https://fred.stlouisfed.org/series/WSAVNS