I, personally, found that having a job itself or "working" on a graduate degree isn't in and of itself detrimental to your running performance, if you are single, and in some cases may even benefit you. Same is true when you don't need money to support a family. Let's say you work 7-9 hours a day, but have nothing else to do...how difficult is that time-management-wise. The situation becomes challenging when you move running to take a back seat because of limited time due to family, and work (not talking part-part time "work"). That is, when there must be a trade-off between time spent on x versus y.
Outside of the top paid professional runners everyone is sub-elite by definition (they cannot rely on running as their only source of income). So what is really interesting is what those that are not paid running professionals sacrifice to be able to run and why. Because to cultivate meaningful relationships, work, ensure spiritual growth, have free time, be involved in the lives of your children take lots of time.
Lot way of saying, perhaps it is a good idea to "focus on training" until you should not any more. You know best when that time comes. Just don't try to impress anyone...