Lost Performative is when someone says something that contains a rule or judgement without anyone taking responsibility for it.  It can include an implication of an idea instead of a direct statement such as “Breathing is good.”  
A suggestion is presented to the subconscious stating that some opinion is true, but does not say how it known to be true, or who is saying it. The therapist intends that the subconscious will accept the statement as being self evident and not ask for proof.Examples:

Your subconscious mind will find the correct answer.
You are never going to have a problem with your nails again.
No habit can stand up to the power of the mind.”

A lost performative can also be an evaluative statement in which the person evaluating is missing, such as:

“It’s not important how quickly you relax” – contains the presupposition that you will relax, and it doesn’t mention who it isn’t important to.
“It’s good that you can concentrate on my voice” – contains the presupposition that you will listen, and it doesn’t mention who it’s good for.
You can always test for a lost performative statement by asking ‘Says Who?‘.