I had considered doing this myself at one point to get to Princess platinum for the quite valuable internet benefit. Unfortunately, I couldn't get the timing to work before my most recent cruise got me there without a "cruise run".
The internet benefit would have saved me several hundred dollars on my past cruises so it would have been well worth it. I don't really see the economics for Elite, however. I'm curious which Elite benefit your husband thinks is worth the expense he's considering?
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There isn't one specific benefit that we're after; just the general benefits combined. At this point, with 6 cruise credits until we reach elite, three coastal cruises are far less expensive (even with the single passenger supplement) than six full cruises. We're looking at it more like a fast-track opportunity to reach Elite.