Ignore that kind of people, own self line noob then proclaim own self pro line, already met these kind of people thousand of times. About lan c... I can say.. 90% of DotA player in GGC will lan c. even if you did nothing wrong. But they enjoy when they lan c u. This is their true entertainment when playing DotA i guess?

Btw, if you don't wanna face these problem. Then just find friends to host and play with them in 1 team