See the top post in another HN thread for my criticism, copied below. When "she" becomes the default, I find myself veering off from the topic at hand to consider gender politics and try to infer the author's intention. Does OP see makers as "us" and managers as "them"? Is OP using "she" because /they/ believe managers are disproportionately male and so chooses a pronoun to prevent further exclusion? An ideal grammar solution should not require the author to disclose his politics, either by omission or commission, just to communicate effectively.
https://news.ycombinator.com/item?id=10658187
"Manager time" is a small allocation. Since the manager's heap only uses blocks this size, she can do this all day without any problems or fragmentation.
"Maker time" is a large contiguous block. If the heap is empty, you can allocate them without any problem. But stick one manager-sized block in the middle and now you've split your heap such that the total time available is large enough, but it's not contiguous. Classic heap fragmentation[2].