On Sun, 2 Mar 2003, Kim & Rima McKinzey wrote:
[Mark Mandel]
#>... "knock
#>on wood", after mentioning an undesirable possibility.
#
#?? I've only used it, or heard/seen it used when it meant,
#essentially thank goodness - not an undesirable possibility.
Oops. I stand corrected. Yes, that's the use I know.
-- Mark M.