This style of pruning is often done as an alternative to aggressive topping.  When a tree is topped the new branches that grow back are elongated with little taper and sparse inside lateral branching.  This results in branches with heavy end weight that are more prone to failing than natural growth.  The large aggressive cuts promote rot and decay that may make the regrowth structurally unstable. Drop crotch pruning in turn reduces the height and overall size of a tree by lightly removing the end weight.  This will mitigate branch failure in the immediate future.  This style of pruning is appropriate for many Mango and Avocado trees that are grown in smaller residential yards of Honolulu.  Often times families planted a Mango tree generations ago on their family property not realizing how large it can grow over time.  With drop crotch pruning, we can maintain a trees overall size while still allowing it to yield fruit year after year.  The alternative is to aggressively “top” the tree which results in having no fruit for 2-3 years.  This style of pruning is redundant because the new growth will be at the same height or higher once it is mature enough to bear fruit once again.  Drop crotch pruning promotes consistency in size and a medium fruit yield.