I've reverted the change twice now where:
- David Munshi was a PhD student in computer science at York University in Toronto, Canada.
has been changed to add "Dr." before his name.
The sentence "David Munshi was a PhD student" means that he was studying for his doctorate. That's what Ph. D means: Doctor of Philosophy. Before you receive your diploma, you are, by definition, not a doctor. Further, Munshi, when met by Simon Jarrett, even says that he's hoping that his work on the gentle brain process as part of a thesis will get him his doctorate.
The person we meet in-SOMA is always Mr. Munshi. Only in the Soma-universe do we (later) learn that he succeeded in attaining his doctorate. I believe we should honor the text itself and refer to him as Mr. Munshi.