Thm* E:EventStruct, P:TraceProperty(E), A:Type, evt:(A |E|)
, tg:(A Label), tr_u:Trace(E), tr_l:A List.
switchable(E)(P) 
No-dup-send(E)(tr_u) 
full_switch_inv(E;A;evt;tg;tr_u;tr_l)  ( m:Label. P(map(evt; < tr_l > _m)))  P(tr_u) | [switch_main_theorem] |