Method and devices for delivering pulsed RF ablation energy to enable the creation of lesions in tissue are disclosed. The delivery of RF energy is controlled such that the generator power setting remains sufficiently high to form adequate lesions while mitigating against overheating of tissue. An ablation catheter tip having high-thermal-sensitivity comprises a thermally-insulative ablation tip insert supporting at least one temperature sensor and encapsulated, or essentially encapsulated, by a conductive shell. A system for delivering pulsed RF energy to a catheter during catheter ablation comprises an RF generator and a pulse control box operatively connected to the generator and configured to control delivery of pulsatile RF energy to an ablation catheter comprising at least one temperature sensor mounted in its tip. Also disclose is a method of controlling the temperature of an ablation catheter tip while creating a desired lesion using pulsatile delivery of RF energy.