Consensus is one of the central distributed abstractions. By enabling a collection of processes to agree on one of the values they propose, consensus can be used to implement any generic replicated service in a consistent and fault-tolerant way. Therefore, complexity of consensus implementations has become one of the most important topics in the theory of distributed computing. We are interested in consensus algorithms in which a propose operation is allowed to apply primitives other than reads and writes on the base objects only in the presence of interval contention, i.e., when another propose operation is concurrently active. Such algorithms are called interval-solo-fast.