The more serious problem is one where the model is taken as an absolute process where the boundaries stop the infection. If a person understands A New Tree Biology with the concepts of compartmentalization and successions, old practices will be quickly recognized as being more harmful than beneficial. Flush cuts on branches remove the tree's protection boundaries and create wounds in the trunk. Painting wounds blocks the normal successions, which stimulate the tree to form boundaries. Callus and woundwood form after wounding.
Compartmentalization is a separate process that takes place in wood present at the time of wounding.
Digging into cavities breaks the compartment boundaries that resist the spread of infections. Drilling holes to drain liquids exposes healthy wood to infections. When wetwood is drained, the wood first infected by bacteria will usually be infected by wood-decaying fungi. As some trees are wounded repeatedly during treatment, the storage spaces for energy reserves is reduced, and defense is also reduced. Many insects and microorganisms attack when defense is low.