Thanks very much, everyone. And BAAZ, I appreciate the comparison. Over the last few years, I've used Eurostar exclusively for this route, but was just curious about how it measured up against the flights when commuting regularly.
Checking prices as far out as the Eurostar booking engine will permit (notwithstanding the special Olympics availability), it looks like Eurostar is less expensive as well. I suppose that settles it… Less expensive and more convenient. In that case, and seeing that I've just had to book one journey, I probably will make the one extra trip to obtain Carte Blanche.