Yeah, anything more than a couple (2-3 metres) from your ears, especially when in front of and facing away from you is cause for worry as far as induced delay is concerned. With the higher frequencies having to make a detour through reflection (like the snare/clap) you are looking at relatively long delays that will throw off your mix.
Obviously the headphone trick will work, but only if your controller/mixer features split cue so you can hear the master mix in one ear and the incoming track on the other.
Those who have followed some of my earlier posts know that I am big advocate of monitors. I always bring my own. Small enough (although slightly heavy :-)) to carry around with the microphone stand it sits on. Mind you, monitor speakers are really only any good when the controller/mixer has a booth out control.
Obviously you can set the speakers behind you, but that is a surefire way to screw up your ears in no time flat. I do not ever stand in front of my speakers any more (another reason is that I couldn’t use the microphone without incurring major feedback).
I use the headphone mix at home to practice when I don’t want to disturb the others in the house or the neighbours, but in real life I don’t want to isolate myself like that, so I prefer a monitor speaker in that case.
Greetinx,
C.