I'm not sure if you've misunderstood Wayne's post, or I've misunderstood yours. Wayne isn't saying he believes the upgrades came from telling anyone of his status, but because the person with the ability to upgrade would have had that information to hand. I agree with him entirely, but I'd add a further category which, in my experience, is often the reason for an unexpected upgrade and that's when it's operationally preferable for the organisation in question. We've had flight, hotel room and car upgrades several times. We've been upgraded from PE to UC with Virgin 3 times. Once I suspect it was was due to the fact I was celebrating a milestone birthday but usually it's either been because we're loyalty club members or, more often, just because it's suited them. Once when we were going to Florida with friends, they upgraded 3 of them to UC. They were actually a family of 4, but their daughter's ticket had been bought at a later date so Virgin's system was showing them as a party of 3. They explained the situation, but the check-in attendant wasn't able to upgrade them all - she'd just got a flag on her screen telling her to upgrade the first party of 3 to check in because they needed to find space in PE for another party. Another time we had a reservation for one night in a two-bed villa at the BoardWalk. When we checked in, we were told that we'd been upgraded to a BoardWalk view which we thought was odd because that's what we'd booked. When we got to the room, we'd actually been given a Grand Villa. I've absolutely no doubt that it was pure luck based on operational requirements and I don't imagine we'd have got it had we been staying for longer. The first time we stayed at AKL we'd booked a Savannah view and I'd requested a king bed. When we checked in we were allocated a family room with two queens and a bunk. There were no Kings available. I asked how much it would cost to upgrade to a Concierge King. That'll be $20 a night, madam. Needless to say I bit her hand off, but she wasn't doing us any favours - it was just the price that came up in her system. Obviously prices had dropped since we booked and we got lucky.
I agree with everyone who's suggested that asking for a free upgrade is almost guaranteed to lead to disappointment. Just put yourself in the shoes of someone who's in a position to hand out free upgrades. Surely even the most saintly, sweet-natured person is going to be a little bit irked by such a request. Conversely, if they have got any to hand out, they'll be more inclined to do so it they like you, so smile when you approach the desk and try to be chatty. Say how happy you are to be there, but don't drop big hints - they'll have heard them all before. There's nothing wrong with asking if they have any better rooms, but I'd be inclined to enquire about the cost and avoid the word "free".