From CT3

Enhanced Interior Gateway Routing Protocol (EIGRP) behaves disappointingly in inadequately designed networks due to the distributed nature of its route computation algorithm (DUAL). Worst-case DUAL computation requires every remote site router to acknowledge it does not have a route to an IP prefix that disappeared from the network due to a topology change.

Cisco has improved EIGRP convergence behavior dramatically with the introduction of stub routers in Cisco IOS release 12.0(7)T and subsequent releases have added support for redundant remote site configurations with the leak map feature.

Read more in the Scaling EIGRP Networks with Stub Routers IP corner article ...