- * Variables also have one field related to concurrency: concurrency_share.
- * In effect, in some cases, one variable is involved multiple times (i.e. two elements) in a constraint.
- * For example, cross-traffic is modeled using 2 elements per constraint.
- * concurrency_share formally corresponds to the maximum number of elements that associate the variable and any given
- * constraint.
+ * Variables consumes the concurrency_limit of each constraint they are using.
+ * Each pair variable/constrainst is linked by a *single* Element object. Through this
+ * object and the respective methods (get_concurrency(), increase_concurrency() and decrease_concurrency()),
+ * the variable changes the constraint's concurrency.
+ * The amount of concurrency slack taken by each variable is determined by the Element::get_concurrency() method.
+ * At the current state, each variable counts as 1 if its consumption weight is greater than 1.