When designing large EIGRP networks, what is the benefit of route summarization when there are multiple paths to the same destination?

Preventing routing loops is the function of EIGRP's Diffusing Update Algorithm and the feasibility condition, not route summarization.

When a specific route within a summary is lost, EIGRP's DUAL algorithm sends queries to find an alternative path, and without summarization these queries propagate throughout the entire EIGRP autonomous system, causing widespread instability. Route summarization contains this query domain - routers advertising the summary absorb queries at the boundary rather than forwarding them - which limits route churn, prevents query storms, and results in faster, more stable convergence across multiple paths.

Load balancing across multiple links is achieved via EIGRP equal-cost or unequal-cost load balancing using the variance command, not through route summarization.

Discarding unwanted routes is accomplished using distribute lists or prefix lists applied to EIGRP neighbors, not route summarization, which aggregates routes rather than discarding them.