Of course I am not a cleric in the Muslim community, so I really have no say in this matter. I belive that it depends on the reason for refusing to have sex. There are some times when it is neccesary for the relationship, even if you are not "in the mood".
I think that what the chaplain said is horrible. It's even worse, since he is believed to be a religious leader, so he can manipulate people into believing almost anything, because they are afraid of sinning and going to hell. I sincerely hope that the people who listened to this man did not believe him, and I hope that he is stripped of his power.
Refusing to have sex is not a sin at all though it may bring trouble in any marriage and be a reason for divorce. The Toronto's Muslim police chaplain based his argument from the Koran, so from that perspective he was right. It is a ''sin'' in countries where Sharia law is the rule of law.
No, refusing to have sex with your husband is not a "major sin." It is every person's right to choose if they want to have sex or not. Just because someone is married does not mean that that person can have sex whenever he or she wants. Society does not work that way.