The first came not in a paper but in the discussion afterwards. I think the comment was made by Amelia Rutledge, following the 'Tolkien & The Bible' session. Trying to distinguish between Tolkien's and Lewis's approach, she said "Tolkien was a Creative Theologian; Lewis was an Apologist". That is, in retrospect Tolkien appears much bolder in proposing new ideas about God and his creation. Lewis, by contrast, was defending current dogma and so devoted much less time and energy into speculation. It's not that his mind was any less creative than Tolkien's, but that he was trying to find new ways for folks to believe in established ideas. I'm not sure the distinction holds, but it's an interesting idea I'm going to be mulling over for a long time to come.
The second came not so much from what the person said as in the juxtaposition that made in my mind with something else I'd been thinking on. Here I think the speaker was Peter Grybauskas who, apropos of something else, observed that in the disasters of 1916 Tolkien was "Left Solitary & Alone -- was that what made him the Writer he became?" (or at least that's how I set it down in my notes; his phrasing may have been somewhat different). I've been thinking about Diana Pavlac's theories of the Inklings as a demonstration of the importance of the impact a writer's group has on an author. But here's a major example of the exact opposite phenomenon: here's it's the writer suddenly being shorn of his writer's group (through the death of two of the other three core members) that provided the impetus for an explosion of creative energy. I think this can be reconciled with Diana's theories fairly easily, but I look forward to hearing her views on this come July.