Beware of theoretical problems

Anybody who was a change agent or acted as one knows this too well. You meet a development team of 15+ engineers and do an introductory talk on Scrum. Even before you are one third through the talk, there is a question or an interruption from the audience - similar to one of the following examples:

• this is all very interesting, but how it [Scrum] would deal with a situation when half of the team quits their job on one day?
• this may work in an experienced team, but imagine that you have a team where there is just one experienced developer and all others are fresh graduates
• I don't understand why you are against my idea of recording the stand-up meetings; sometimes the amount of input from the team may be too large for the Scrum Master to remember

If you hear that (and it could be on any meeting you talk about change, not necessarily about Scrum), don't engage into discussion.They are all extremely theoretical questions that will NEVER happen in real life. What's more, whatever process / approach / tool is used today, it is most likely unable to resolve these theoretical problems either. As a change agent, you just have to hear it out, but don't begin discussing it.