Concerts sell out in minutes all the time. It's not impossible. The biggest problem with the Binance ICO is the lack of cap. Whales loves that while it clearly hurts us.

The warmup session for TRON sold out in <5 seconds. I'm not surprised.

While for the main TRON BTC session they were selling 380BTC worth of tokens (0.00000038 BTC each token). If each whale put up 5 BTC (pennies for many), it would only take 76 of them to sell the whole session out. And what if some of them bought 10 or 20BTC worth of it?

How many people do you think were trying to take part in these ICOs? How many people were sitting in front of the computer at 11:59:59am Beijing time, ready to place an order? 500 people? 10k? 50k? 100k?

Even if you don't know what is it that TRON or LLC do, just for the potential speculative value, it's clear to me how those ICOs could have sold in seconds. No mystery.