Well having read the thread it went the way I thought it would. 
Mitchy - the short answer to your original question is that I post here because I am interested, because I can and because I want to. I have been on MN long enough to know some women dont want men here or indeed on MN at all. Unfortunately for them, no one appointed them as Feminism section police so they will have to live with me making an occassional post.
The longer answer relates to the comment rosabud made earlier " it's a shame we don't see more men posting about other topics which the wider subject of feminism touches on such as parenting/equal pay/ family breakdown/ representation of women in the media etc etc."
I dont know where she has been looking but I have posted on all of those topics this week. I really don't care which section heading a thread is under.
The thing is though, nearly every subject could be looked at from a feminist perspective, or from a wider society perspective or even just a different perspective. Just because an MN post defines it as a feminist issue doesn't mean it is only a feminist issue. If it of interest and I have time and I think I can post something reasonably interesting then I will.
Feminism is just a column header in the MN Talk database when all is said and done. To me, what matters is not that thing called 'Feminism' but that thing called 'Society' and making it better for everyone and most especially our children. Women/girls are at least 50% of that society and suffer unfair treatment in nearly every aspect of their life. A very important part of making society better is obviously removing the unfairness women face. Men have to be involved in that process (self evident truth) and we (men) have to be able to discuss the issues if we are ever going to make it happen.
I don't post in Feminism that often and I read many threads and make no comment at all - which is my version of 'shutting up and listening'. I will keep posting though and I am not going to 'shut up' if I disagree or have something in my 49 years of life experience that is relevant to say.