The good thing about the K system is the built in headroom. If you are working at a K -14 ref level then it means your rms part of the signal can actually go almost 14 db above your nominal signal level. But that also depends on the size of the transient that is attached to the front end of it.
 
But even so a shift of +4 over is not going to harm anything.  It is just your rms component jumped up 4 dB but there is still 10 dB of headroom above that.  Don't let the +3 dB max scale of the VU meter throw you. There is still 11 db of headroom sitting above that mark even. (at K -14 that is, at K -20 there is whopping 17 dB of headroom above that + 3dB mark!) Hey, get to love K -20!
 
I work with a magician here and I do all his music/sound effects. The music all sits at K -14 actually but I have a full 14 db of headroom.  I can put in an explosion that might go 12 dB over the music but it will still do so without clipping into 0 dB FS. Only for a short time but through a big PA it sounds pretty amazing.
 
But your rms levels should really never be peaking +8 or even +4 db over much at any time. With care you can control the dynamics of signals on tracks and busses so they still carry all their dynamic range and transients but mainly hit 0 dB VU and not go over by more than + 1 or 2 dB. That is achieved with careful setting of dynamics processors in these places.

Check out this informative article from  Sound on Sound Magazine from last May:
 
http://www.soundonsound.com/sos/may14/articles/reference-monitoring.htm