I have a family member in the US that is part owner of company. A majority owner was leaving and so that presented an opportunity for me, in the EU, to send them $50k to invest. I could take profits from BTC as an early adopter or I could dip into FIAT savings. The former seemed ideal and seemed to be perfect for BTC according to the prophets. So I started looking into how to do it. On the US end MtGox can be used but with a long delay for 4 to 8 weeks and some marginal fees (0.5% exchange fee, $10 transfer fee). A bit ridiculous. But the other exchanges are worse, in a different way. For example Coinbase has 2 to 3 day transfer but a daily limit of 50BTC. That means it would take at least 9 days to sell enough BTC to convert into $50k. Assuming all these abstraction layers work out it would take 2 weeks to get the money with some fees for exchange (1%). CampBx doesnt really state their BTC sell limits clearly but do state a $1000k per day withdrawl limit. 50 days is nuts. Guess there is a wire transfer option but not knowing the BTC limits its just not clear if this would work. A p2p exchange such as #bitcoin-otc would have a 5% margin from my experience so this also seems a bit much. Localbitcoins and in fact most of the other exchanges have such low volume this also has to be considered.
I hate to break it to you, but your argument is totally bogus, and the headline is downright misleading. If you want to replace it with "Stop saying Fiat is good for money transfer. It isn't." then, I will happily agree with you. Because in all these different examples, you are talking about transferring from Bitcoin -> Fiat -> Fiat, which is not at all the same as Bitcoin -> Bitcoin like in the traditional way this money transfer argument works.
The argument that bitcoin is good for money transfer is still intact, and valid, even if you are using exchanges like in your example. Want to transfer $50,000 worth of bitcoins from Coinbase? Go right ahead, I just looked this up on Coinbase, there's no limit on the amount of bitcoins you can send from your account. As long as you have that many bitcoins, you can send them. I could do the same from Armory and send any amount of money I like to anyone else in the world and they'll get it within an hour, most of the time. Even if it's Sunday. Try doing that with a Bank.
That isn't what you're talking about here. You're talking about Bitcoin, but all you mention here are exchanges which means you'd be getting your fiat money out. So what you're really talking about is cashing out and transferring money in Fiat. That's always been a pain, and there's nothing Bitcoin can do to change that. Even if Coinbase had an unlimited withdrawal, keep in mind that your bank might flag the transaction because you're talking about an amount of $50,000 and (at least in the United States) by law Banks have to report any transfer of money that's over $10,000.