I just want to add on that I believe debates are good for relations among individuals because it allows us to expand our minds, and understand different perspectives. That being said, even when debates aren't constructive, I think it allows us to understand the people surrounding us, debating with friends/potential friends exposes us to who they truly are.
Healthy debates among individuals is good for human relations in general, so long as the debate doesn't devolve into bickering and name-calling. Debate fosters honesty, truth-telling, respect and a free exchange of ideas among interested parties. Debate and dialogue are starters for compromise, the only way things get done in America.
Yes, debate allows for good relations among individuals, because it allows people to learn about each other. People debating can find things that they have in common, and appreciate differences. People can disagree with each other without disliking each other. Debate allows people to find common grounds and strengthen friendships. People will learn to appreciate each other despite differences.