Wielding the Flame of Anor

[HerenIstarion]

A lot of interesting speculations up there, which, for all we know, may be true.

only

Oh and personally, I think Gandalf knew he'd kill the Balrog when he stopped on the bridge.

meets some objections. For why than such a talk as "and I'm already weary"? Was Gandalf trying to higher his marks in his companions eyes? Say, he knew he was going to kill it, yet he was faking uncertainty, to get flapped on the back in a more appreciative way afterwards?