It does not become silly just because you "think" ... there are some people like me (although in the minority) do play with dual systems ... but once again that does not make it "silly", it only means that you "think" it is silly i.e. it is all in your head and is not real.
You chose Canon for a reason, I respect that but calling others silly bcoz they don't do what you do is actually silly. Just like you "have more time for Sony rumours", some of us have the time and interest to play with dual systems.
(BTW, I did read your rebuttal in a later post but whatever your reasons are, just bcoz you "think" it is silly does not make it silly ... a small secret, we all "think" many things but some of them are not real )
Are you mainly shooting international sporting events or landscapes/weddings etc?
As my first post was really pointed at the sports pro. If landscapes then of course it does not matter as much.
Perhaps I chose a wrong word, when I used the word "silly". But I still do not think it benefits the photographer (especially pro sports photographer) to have two DSLR systems each with their own lenses.
That is my opinion, and that is what forums are for. But you are right just cos I think one thing, does not make it right, or wrong. I am pleased you admitted you are in the minority - and there is a reason for that.
Added: and the reason I mentioned Sony, is I could imagine having a small camera like the RX1 in my bag with me, which would mean I too would be then using a dual system. But what it does not mean, is I would be investing in glass for that system, because I would still only use Canon for that - unless I decide to change and go to Nikon or another brand in the future. I would not invest in two different DSLR systems that require lens investments.