It's a good exercise to try and fly the a/c without it's primary controls. I woudn't try it for the first time in the circuit though!
The scenario could be quite real, what if you had a control restriction? A mixture of power, rudder and trim is quite an effective way of controlling an a/c, but you do need to be very careful and make all inputs gradually and smoothly.
Don't try this on your own for the first time, but on your next flight with an FI get them to demonstrate it and have a good go.