statistics/2: choice needed

[UWN]

The value of choices in statistics would be very helpful, if available via statistics/2. After a certain point, it seems that choice points are no longer removed.

Also, it would be nice to clarify the precise meaning of choices. Consider:

?- (X=1;X=2),statistics.
Goals 2, Matches 0, Max frames 0, choices 0 ... % why 0 choices, there is one alternative!
   X = 1
; Goals 4, Matches 0, Max frames 0, choices 0 ... % here, 0 makes sense
 X = 2.
?- (X=1;X=2),(true;true),statistics.
Goals 2, Matches 0, Max frames 0, choices 1 ... % finally a choice(point), but why not more...