Watch the Club 54: 4 online guitar lesson by Chris Buono from Guitar Cubed
When it comes to playing a series of four 16ths within one beat only to have to choke the strings on the following downbeat you have two ways you can "deactivate" the strings. One works well while the other has its problems. First, the problematic one: You could choose to just simply release the fret hand pressure that’s pressing the string against the frets thus cutting off the vibrations. The problem is you may cause a sympathetic, a single or a series, of harmonics to begin ringing depending on what portion of the neck you're in. You could even just release the pressure and take your hand off the neck completely but that will almost definitely leave open strings ringing making the part come off as sloppy. The reason why I stated the wrong way first is because in order to counteract the second of the two not-so-good approaches is actually the best way to do this and that is to just put your pick hand down on the strings as seen here!
Move on to the next segment to see what all the fuss is about in regards to stacked fourths among other things.