turns out that the reason behind this odd behavior is that one of the ids mentioned in the add/removeItem where misspelled but the log was pointing to the wrong line.
I had this
$( '#edit_contest' ).parsley( 'removeItem', '#prz2_it_ttl' );
$( '#edit_contest' ).parsley( 'removeItem', '#prz2_en_ttl' );
$( '#edit_contest' ).parsley( 'removeItem', '#prz2_it_des' );
$( '#edit_contest' ).parsley( 'removeItem', '#prz2_en_des' );
and the error was pointing to the 1st line when the real misspell was on the 4th line. after discovering and fixing that, everything started to work like a charm (more or less). so the moral of the story is: ALWAYS double check all the ids before doing anything else in your debugging routine.