Direct Answer
Based on the transcript, the “pressure” box is often a single atonement theory that claims to explain everything (he mentions Christus Victor reductionism and also penal substitution), and the cost is that other scriptural strands get sidelined. The speaker’s warning implies that keeping one box intact can push out themes like Christ’s descent into Hades, deliverance from Satan’s power, cleansing that depends on “walking in the light,” and even Jesus’ teachings as part of reconciliation.