Synergism
Synergism is the view that God and human beings both have a role in salvation. The term can mean that God's grace and a person's response are both necessary, but it does not by itself establish that the human response earns salvation or shares in Christ's saving work.
Expanded explanation
Synergism is often presented as the opposite of monergism. In the debate, however, the terms can be answering different questions. Monergism asks who performs the saving work. Synergism asks whether God and a human response are both involved in the process in some meaningful sense.
Decalvinised does not affirm synergism as the idea that people cooperate with God to produce salvation or contribute part of the merit. God does 100 percent of the saving work. Christ alone provides the atonement, grace initiates reconciliation, and salvation rests entirely on what God has done.
People nevertheless must respond to God's provision through faith. Faith is not a work and does not make a person a co-savior. It is the receptive response to the gospel. A person who accepts a gift has not purchased it, improved it, or shared credit for producing it.
This is why Decalvinised can affirm a qualified form of monergism while also affirming that human faith is necessary. God alone saves, while people are responsible to receive his saving provision. The disagreement with Calvinist monergism is not about whether God deserves all glory. It is about whether giving God all glory requires him to determine every human response.
Context
The disagreement depends heavily on how the terms are defined. Monergism can refer to who accomplishes the saving work, while synergism can refer to whether a human response is necessary for receiving that work. If synergism means shared merit or shared saving power, Decalvinised rejects it. If it simply means that a person must respond to God's grace, then the issue is not whether the person saves himself but whether faith is a genuine response.
Calvinist arguments often say that God must do 100 percent of everything, including producing the act of faith, for God to receive all the glory. Decalvinised rejects that premise. Faith is not a work, and receiving a gift does not make the recipient its co-savior. God receives all glory for providing and accomplishing salvation even when he holds people responsible to receive it by faith.