I have a hard time asking hard questions over the phone since (1) it's harder for me to assess the candidate when they're only answering verbally (without whiteboard) and (2) they can always cheat.
@Beeisfor: it's common knowledge that cheating is rampant and blatant in India, so much that parents climb into school windows to help their kids cheat: http://www.bbc.com/news/world-asia-31998343
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