I think it depends on the person and on the history of that relationship or all their past relationships. What were they based on? How or why did they end? Me, personally, I don't really keep in touch with my exes. I mean, they are my exes for a reason. No chemistry, no intimacy. I mean, none of them ended badly, it just wasn't a good match/chemistry. For someone to be really good friends with their ex is suspicious because that means they share intimacy. Intimacy is hard enough for relationships, but to have to share intimacy with an ex, isn't really fair to the other person. Hence, this is where all the insecurity, and if you wan to call it jealousy transpires. It's no fun to feel that even if your typically not a jealous person, but it happens to the best of us because we begin to doubt. So in all fairness, as many have mentioned it is only fair to cut off ties with exes.
On the other hand, if I were to keep in touch with any of my exes, it shouldn't/wouldn't be a problem cuz I am SOOO over everyone in my past. But, I don't keep in touch with them for just that reason, there is nothing there.
I'm not saying he shouldn't be talking to his ex, shouldn't be friends with her or anything like that - but that is worrying, or at least it would be to me. Seriously, how do you think his ex would read that? It just sounds so suggestive.
I think people can be friends with their exes if there's no feelings left/no baggage, but it's so rarely that simple. I don't really talk to any of my exes, neither does my boyfriend. It's just how it's worked out, and it works well for us. It's not a 'we can't talk to exes' rule, it's just how things have gone.
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