the guy showed that the SSDs defrag in less than 3 seconds.
i had followed a argument which said that SSDs do not need defragmentation because the ones based on RAM do not get fragmented and the flash based ones are on the other hand harmed by the defrag because it performs I/O operations which limit the lifetime of flash based devices.
in reality: defragmentation is not "necessary" for SSDs as the performance is not affected being address based.
this link actually explains a lot about SSDs and defragmentation: