> It’s very rare for code to allocate exactly the same type of object many times in a row, so the class of the instance local variable will change quite frequently.<p>That’s dangerous thinking because constructors will be a bimodal distribution.<p>Either a graph of calls or objects will contain a large number of unique objects, layers of alternating objects, or a lot of one type of object. Any map function for instance will tend to return a bunch of the same object. When the median and the mean diverge like this your thinking about perf gets muddy. An inline cache will make bulk allocations in list comprehensions faster. It won’t make creating DAGs faster. One is better than none.