‘Matching’ level of correction to behavior

Hi. In the past we've basically modeled a 'matching' style of correcting, where our level of response matches the level of misbehavior from the child. It's from TBRI. At the advanced levels, you don't shout or anything, but you speak more seriously, lower, and slower. Where at the first level you can give a playful correction, [smiling] "Can you try that again".

Using TSG, my wife sometimes corrects my corrections of the kids because, in an effort to stay calm, she says that I come across as almost lackadaisical. Like their disobedience doesn't really matter, isn't destructive, etc. When can staying "calm" in this way as a parent send the wrong message?