When I was in Germany my hosts took me to a neighborhood pub that had a one lane bowling alley in the basement. They play a for of bowling called Kegel or 9 pin. They play3 different versions of the game. The traditional where you roll for high score and the non-traditional where you try to get the fewest pins without throwing a gutterball. Plus they have 3 different size balls from softball sized to one about the size of baseball.
Rolling the ball slow will only get you in trouble as it is allowed that an opponent can get up at anytime….run the the alley and kick the ball in the gutter. If he is successful you get a hashmark on your score….if he misses, he gets the hashmark, Hashmarks matter because at the end of your bowling outing you pay by the hashmark. At that time it was a Pfennig per hashmark.