1. A full roller is someone who has zero or almost zero degrees of axis tilt. The oil track on the ball will generally pass between the thumb hole and the finger holes. I believe that Bowl1820 posted a good diagram of this a week or two ago.
2. You can work on getting a pendulum swing anywhere you have room to swing your arms. There is a weighted arm swing drill where you stand as if you are about to go into your slide; slide foot forward, the other foot 12" to 18" ( for an adult ) inches directly behind, knees slightly bent, upper body tilted forward about 15 degrees. Take a 3 to 5 pound weight in the hand that you bowl with and let it hang by your side, swing the weight slightly forward and then let gravity swing the ball back and forth. You could also do this with a bowling ball but then you should use a sling, a.k.a seesaw towel, to avoid getting in the habit of holding on to the ball past the release point.
3.Assuming that you have good practice habits, i.e. you go with a purpose or a plan for your practice time, not just throwing three or four games trying to get strikes, the more practice the better. Most of us don't have either the time or the money to practice as much as we should. It is possible to practice too much. When you start losing your focus, you need to take a break. If any thing starts to hurt, you need to stop an possibly take a few days off. After muscles have been used the need time to build back up, a day off every other day or every third day helps with this. Our brains retain things better if they are exposed to the information to be learned repeatedly over time at random intervals rather than being immersed in the subject for one long stretch. In other words its better to practice your free arm swing fro 15 - 20 minutes every other day for a week than it is to practice it for an hour to an hour and a half once a week.
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