Sure, when a tree is mature and fruit production begins to diminish, stress can change the mode of the tree. All organisms have different strategies and tactics, but a similar goal, to push as much of their genetic matter as far into the future as possible. A tree in great growing conditions maximizes the overall amount of genetic material by growing as large as possible. It ends up with more total fruit production over a lifetime. If a tree is under stress, it can change strategy. If a tree thinks it could die soon, it can divert energy into producing as much fruit now as possible. If a tree really does have a short amount of life remaining, this strategy maximizes the amount of genetic material produced over that limited life span.
The trick is to make a tree "think" it is in danger without actually putting it in jeopardy. Folks use various techniques to accomplish this including scoring.
Thanks,
Jack