Your btWrong code works correctly in Delphi, so I think this should be considered to be a bug. On the other hand it is easy to fix (by setting the caption before hiding the labels). If there were a bugreport for it I hope that nobody would pick it up and try to fix it because setting the control size and AutoSizing are among the most complex tasks in the LCL, and there is a high risk that this fix would break something else
Just my two cents...