Recently I tried to Access a textbox from a thread (other than the UI thread) and an exception was thrown. It said something about the "code not being thread safe" and so I ended up writing a delegate (sample from MSDN helped) and calling it instead.

But even so I didn't quite understand why all the extra code was necessary.

Update: Will I run into any serious problems if I check 

Controls.CheckForIllegalCrossThread..blah =true
multithreading thread-safety definition
Edit
Report