Question about DBCC TRACEON(1222,-1)

We are having deadlocking issues on a prod server. I was going run DBCC TRACE ON(1222,-1) on the server and then read this on MSDN:

"Use DBCC TRACEON (trace# [, ....n],-1) only while users or applications are not concurrently running statements on the system."

(http://msdn.microsoft.com/en-us/library/ms187329.aspx)

Huh? Our deadlocking issue is triggered by user action. Running it after hours won't be of use

Any comments on that one?

TIA,

edm2

P.S.  I also plan to use DBCC TRACEOFF (1222,-1) when done with the tracing.