TRC was flooded with hashpower, I think they 51%'ed it as well to orphan other miners blocks. The difficulty was jacked up through through the roof, then then left.
https://bitcointalk.org/index.php?topic=261986.0This is the downside of short interval difficulty adjustment. The two week one on bitcoin may be annoying but the short ones are open to far more abuse.
No, it is the result of having a pump and dump scam coin with little network support ...