Exactly--the insights may be 100% right, but are not real until the client is ready--on the threshold--to discover them themselves. I've read that Ts who see the benefit to working in this way send out "test balloons" to help them assess when that moment of readiness is about to be.
I find it to be very similar to the pedagogy I use in teaching: presenting content to students is easy, but developing them into autonomous learners takes a much more intuitive and recursive approach--and at the conclusion, they own their knowledge because it really did come from inside themselves.