"Hey I was thinking about your project, I think it's great, just one condition, this one part, instead of the way it is, I think the opposite would be totally awesome."
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"Very good presentation, I am just concerned about that one part that was not exactly what I expected."
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"Very good presentation. I have no further thoughts about it at all."
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"Very good presentation, it brought to light seven things I think you are doing wrong."
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"I was wondering... was it ever considered... to not do this, but instead do something more innovative and more new?"
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"Hmm, this way seems too controversial. Not with me, but with this guy I know."
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"I can't think of how exactly it should be, but I wish it was different."
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"Maybe instead of being unusual, this should be just like what we already do, and I would feel better about that."
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"I don't have any concrete requests, I'm not going to be like 'You must do this thing I want.' No no nothing as bothersome as that. I just want to keep an ongoing conversation going, I just want to make sure that you commit to getting my approval for any change you do or do not decide to make in your plans in the future."
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"I'm not happy with this project. I think the initial launch should be much more ambitious."
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"I'm concerned because this reminds me of something I have seen before."
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"Before you do anything else, could I provide you with a list of people who might have an opinion about this, and then you go check with them to make sure they think this is a good idea?"
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I wanted to make this post just one long "AAARRRRGGH" but I figured I should flesh it out in some more detail.