I think these 12 hours is a real problem for following reasons:
1) The fix concerned security and as such it had to be adopted immediately. Someone citing "emergency" character should understand this is rather aggravating circumstance, not an excuse.
2) They must have had the sources before released binaries. What was the reason/purpose for not disclosing them for 12 hours? It had to be done intentionally. Are there better and worse players, some who award the security and the rest that do not?
3) Do you think an exchange or any other serious company can work straight with binaries, especially unsigned? Aren't their operators supposed to audit the sources?
4) How much can a crypto change it's value within 12 hours? Can you imagine such a rapid change while all your assets are frozen and you can't do nothing because all major exchanges disabled your wallets? Isn't it like someone deleted your Bitcoin by erasing it's value while locking it "temporary"?

I have not yet got involved in BTC vs. BTU discussion till now and my opinion is not partial for that.
Did BTU team give any explanation for that what has happened? Did they encounter HDD failure?
Do they find such a practice normal and are going to exercise it in the future?