hiya, thx for those who replied.
the how-good-ami-i question, was just because i see many players talk about A B C D class, and i had no idea what that physicaly ment.
now some answers.
i do brake the pack like in a 8ball game.
if i pot a ball and dont got good position: i dont just blow everything around. i mostly train combo shots for my 9ball game. or cussion first before contact, jump shots. whatever comes around. remember this is NOT A MATCH or NOT A STATMATCH FOR MONEY. u are practising.. the stats are just there to give u a indication of how u are improving. ofcourse i could just smack all the balls and hope one would drop , so my stats would look better.. but whats the point? when coming home, no one will give me more money because i missed less balls. its all about practice, and if u can practice jumpshots, combo's etc ull have trained shots u can use for other pool games.
if i dont pot a ball, no idea why, but i made the rule up, to not pot this ball straight away again with the new position. i just continue to play like if it was potted and pot the ball i played the position for.
missing avg 2 shots / rack doesnt sound elite, but u got some things to remember.
1/ this is a average over 25racks.. sometimes there is a rack that just is completly wrong for running out. bad brake, balls stuck together, balls plocking many pockets etc. it really hapens sometimes that i dont got a pottable ball even if i wanted, and i make a 6ball-miss-rack. meaning ill have to do 2 runing outs to keep the average at 2. ull find it out when doing the drill.
2/ your concentration level for 350 balls isnt as good as a first to 50 or 100 match. u lose concentration pritty easily. i found that with myself, my worst runs are at about 3/4 of the 350balls. the last runs are usually very good, as i know ill be driving home soon, and i want to quit the poolhall with a good feeling, so my concentration onthe last 3 4 racks is mostly high. but those right before it are hard.
i usually do 25 racks in about 1.5-2 hours. wich isnt really TO much or TO low for a practice, but exactly the amount of time i like to train in 1 day. (i do have a very quick playstile... im no mechanical player when i train, (weird but im mechanical when im playing a match).
id suggest to try it all out for 1 day, and see what your score is. good luck to all.
edit: ow one thing; to make it ever harder, u can use the rule to only be alowed to pot the ball u played for. even if u overrun it or anything. the ball u played for is the only one u are alowed to play for. (i dont use this

to hard yet)
ps: im was doing 100misses/25 racks when i started pool, after 2 months im at 60-70. hope to do 30 misses at the end of this year... so avg for me is around doing 10 misses/ month less wich is very satisfying i think