Apparently, it's a fairly standard technique (e.g. this review) which is not all that new.
"It is also possible to apply a series of pulses at rates of up to 50 Hz (this is known as repetitive TMS, or rTMS). This procedure is more dangerous and can cause seizures even in healthy subjects; because of this risk, safety and ethical guidelines must be followed [Wassermann EM: Risk and safety of repetitive transcranial magnetic stimulation: report and suggested guidelines from the International Workshop on the Safety of Repetitive Transcranial Magnetic Stimulation, June 5-7, 1996. Electroencephalogr Clin. Neurophysiol 1998, 108:1-16.]"