I think it's often the right tool. My personal flavor involves wrapping the printf() with a conditional that depends on the current function name and the value of an environment variable. I've been trying to figure out how best to write a generic macro for this in x64.

You might be interested in Josh Haberman's post on using GDB's "breakpoint command lists" as an alternative to actually putting the variadic calls into the assembly: http://blog.reverberate.org/2013/06/printf-debugging-in-asse...