I think I'm with Ari and RP. I can't just turn it off and I do want to know why. I think maybe if it was a really brief thing, like under 2 months, I might not need much of an explanation to feel closure. I think if you've been serious with someone it's only considerate to give them an honest explanation, even if it's as simple as "I no longer have feelings for you." I think most of us can tell when some one is feeding us a line of bullshit and it's pretty disrespectful and demeaning in my opinion.
And it is really hard, I've found, for me to be around someone that I have romantic feelings for when it's just platonic. It takes a long time for that to subside in my heart. I like the idea of taking 6-7 months off and then going from there.
Sometimes it can be good to know because it can help you improve and grow. And in our culture, it's pretty commonplace for people to be really passive/aggressive and hold in their issues and then one day just bolt because they were really unhappy. If they had said why, maybe it could have been solved?
There's also a continuum between cutting off ties/no explanations and someone not letting go/texting/contacting some one all the time wanting to talk about it. I like to think there can be healthy discussion about it without going over board.
I just can't wrap my brain around being close friends with my ex. The feelings are way too raw and that was back in February. Not to mention how shitty it ended. Some one recently said something like... If someone treats you like shit in a relationship, then why would you expect them to be a good friend to you?