Years ago we all used 13mm+ tips for games like stright pool, eight ball and other games where we thought we needed more control. The larger the shaft size ment a stiffer shaft and the smaller shaft had more whip and any time you used english with a smaller whipper shaft the less control you would have. Almost all the good straight pool players years ago used 13mm+ shafts because the name of the game was control. But along came the preditor shafts that were smaller but because of construction they were stiffer. A dime shaped tip on any sized shaft has the same amount of contact just smaller shafts are harder to control if the shaft is whipper. Just felt like puttin my two cents worth in.