Any appendix Howell movement is in effect a ¾ Howell movement, as all pairs do not meet all other pairs.
Even so, there are more effective ¾ Howell movements than the appendix table versions; these eliminate the sharing of boards. The method of derivation of the ¾ Howell is the same as for the ordinary Howell with the proviso that the base skeleton and the super skeleton include more than one idle pair as in the case of the standard Howell where pair 1 is the only idle pair in the skeleton (being positioned opposite a stationary pair).
For example base skeleton:
(14)-1 5-7 4-3 12-6 10-2 9-13 (l5)-8 (16)-11
Super Skeleton:
(14)-1 6-8 3-2 10-4 7-12 5-9 (15)-11 (16)-13
SS - BS give the following starting positions respectively:
1 2 13 12 11 10 4 3
Giving the following ¾ Howell:
14-1 6-8 16-13 15-11 5R 5-9 7-12 10-4 3-2
Or one round later for neatness:
16-1 15-12 5R 6-10 8-13 11-5 4-3 14-2 7-9
Note 14, 15 and 16 are stationary.
The advantage of the ¾ Howell is that there can be a predetermined number of boards in play irrespective of the number of tables up to a number equal to the number of sets of boards less one. If the number of tables equals the number of sets of boards then the movement could then be called a half Howell and is in fact a Mitchell movement.
