Anyhow, I have an idea about scrapping parts from worn out aircrafts was one of the mechanics finest abilities and might have kept more planes in the air than actual aknowledged!
If I recollect correctly the phrase used related to Christmas Trees. If an aircraft was Christmas Treed then it was to all intents and purposes available as a source of spare parts. When the brown stuff hit the fan was when a decision was made to bring it back into service.