[fishywang]

indent/dedent: how is it less efficient using handwriting than using keyboard? If you mean the case like you realized that you need to add an if to add another level of indention, any interviewer/company requires you to wipe the whole thing and reindent properly on the whiteboard is not worthing working for anyway.

cut-paste: if you are doing this a lot, you are doing it wrong.

refactor: sure. but for whiteboard interviews, it's rarely needed, or it's small enough that you can just wipe and rewrite it again on another part of the whiteboard.

Of course, all these points are assuming that the interview question is "suitable" for whiteboard interview. If you find yourself need to write more than 100 lines of code on a whiteboard during for an interview question, at least one of the interviewer and interviewee is doing it wrong.