I switched from a technique-based art, Judo, to a more concept-based art in Tai Chi.
In a stand up grappling for Judo, I may attempt a technique that I am more comfortable with, let's say a Tai-otoshi against an opponent. To achieve that I would go through the steps in the technique, ensuring I break the opponent's balance by pulling his sleeve, placing my other arm against his chest while stepping into the correct stance in relation to his position to execute the throw. The success of the throw depends largely on the correct applications of the steps in a technique and timing. There are different ways to move into a technique, but in execution the form must be adhered to for maximum efficacy.
In a similar situation for Tai Chi, I would ensure my own equilibrium and rooting, instinctively feel for the imbalance and involuntary rigidity in my opponent. In my mind there are no steps or prescribed technique, instead I would try to remain as relaxed as possible and move my opponent into 'emptiness' using trained non-muscular torque or springing force; this results in throwing him off balance or straight down on his face if successful, and it depends on conforming to the principles of the art against normal instinct. The execution of a takedown may vary in its form but the underlying concept remains unchanged.