If both parties are polite, without thinking about it, they would step in front/behind their respective partner so neither party has to step in the road etc.
Unfortunately, not many people seem to do this, and expect you to step aside or wait for them to pass. It is something which really bugs me, as to how ignorant many people are about this.
Now I have resorted (if I can see that the couple [and sometimes 3 or 4 people] are not going to move aside/single file) to standing my ground, even if it means them hitting against you! I know 2 wrongs don't make a right, but I am truely fed up with peoples attitude on this.
Well, have got that off my chest!