for some year I written some posts about classical guitar tremolo technique on the guitar forums. Here are a few :
"I think when you play with rolled chord technique your fingers goes down one after another, without jumps: pima - The same thing happens with the Tremolo p,a,m,i because, even if you start with your thumbs (p), it is like you start with the ring finger (a) : a,m,i,p (so it is easier if you think of starting with the ring finger)"
"...However variants of the tremolo are useful to play well the tremolo,
they are a good work but then the tremolo should be played p,a,m,i"
"When i was young I studied very slow with the metronome for a while, increasing day after day speed.
.... it is also useful to study classical guitar technique separating the two hands if your problem is the cleaning chords .
in any case the tremolo technique is a virtuosity and need a lot of good will and determination to achieve a good result."
"Tremolo requires a daily practice for one year at least and it is impossible to begin with a difficult piece as Recuerdos de la Alhambra.
I remember one of the firs tremolo exercise I studied was composed by Reginald Smith Brindle ( book: Guitarcosmos number 2 , Schott edition ).
I post some tremolo exercises on my free web site at this link http://www.classicalguitarvideo.com/teachpag/tremoloexercices.htm
and now I composed also a tremolo piece " Sea of Tranquility "
Sea of Tranquility by Daniele Magli
You can find the free pdf score about Sea of tanquility and all my classical guitar compositions at this link :
Another useful page is "The right hand" : http://www.classicalguitarvideo.com/teachpag/righthand.htm
I will post more about classical guitar tremolo rolled chords and rasgueado as soon as possible !