Cross-layer mechanism, for which a protocol locating at a given layer uses information issued from other layers, may enhance the mobile networks performance. Some of those mechanisms are based on mobility metrics. For example, the establishment of a route by choosing less mobile nodes could improve the routing protocol. In this paper, we study the ability of mobility metrics to reflect the mobility influence over the protocol performances. The proposed approach evaluates the ability of a metric from its capacity to indicate or predict the routing protocol performance. Three routing protocols are considered: AODV, DSR and OLSR. The studied mobility metrics are Frequency of Link State Changes (LC), Link Connectivity Duration (LD) and Link Stability Metric (LS). The metrics are evaluated by simulation, firstly in a general case then in a scenario case.