Madam Speaker, the member for Regina--Qu'Appelle is an experienced member and he knows his history. When prime ministers or party leaders refuse to sign nomination papers, there is a great possibility that the person will still run and succeed as an independent or switch to another party.
The reality is that because of the constituency system any leader has to be careful. If an individual MP is very popular in his constituency, because he has done a good job, then that MP cannot be wished away as easily as someone failing to sign his nomination papers.
As for appointed candidates, the record on appointed candidates is pretty clear too. They do not tend to last very long. The prime minister or party leader can appoint candidates but so often they do not survive for very many elections. On the other hand, if someone is genuinely grassroots in our constituency system then watch out.