He can sense your attitude: you have a standard, which is not necessarily his. His trust in you is thus eroded. He cannot count on you to promote his agenda/interest. So he suggested you talk to him in private.
Your co-workers sense that too. So they don't have to take what you have to say seriously.
When you have a "standard" that is away from yourself, you may feel righteous that you adhere to a higher merit. But at the same time, you may have "lightened up" yourself by off-loading that burden onto some "ideal." As a result, you have made yourself a "light-weight."
If you say to yourself: I am the standard, and align that to your boss's, your office life would be more smooth-sailing.
that your tone needs to change when talking to your boss, instead of just telling him what went wrong, can you somehow show to him that you have his best interest in mind, rather than showing how correct you are.
Do not sound frustrated, irritated, or contemptuous. Smile a business grin. Sometimes, a hint to the problem is enough. If that piques his interest, you continue, otherwise stop.
Whether he adopts your idea, that's his problem. You've done your part.
Came across it this morning, a good reminder:
"You will never have a greater or lesser dominion than that over yourself...the height of a man's success is gauged by his self-mastery; the depth of his failure by his self-abandonment... He who cannot establish dominion over himself will have no dominion over others." -- Leonardo da Vinci
同事多次说一些和事实不符的事情。前天小组会有说了一件事不能直接完成，一定要要先挪数据。其实，根本不用，可以直接做。老板不懂，但是估计即使知道他错了，他也无所谓，或者为了显示他老板也是懂的，他就会替这个同事胡说八道解释一通。虽然他跟我说过， 你有不同意见私底下告诉我。
我很纠结，不知道如何处理。我只是觉得这样很不对。我是想给老板email，告诉他正确的做法，这样有个记录，以后发生什么事情可以有凭证。有时候觉得算了，让他去，说了我也没有好处，老板为了平衡也不会做或说任何事情。
请教你的高招？
NASDAQ 涨势不减，美国经济走出低谷，而代表IT业的S&P500持续低迷，IT就业市场继续走低，裁员减薪趋势不可逆当！
IT学子用垂不朽！
Are trying to help but end up taking big hit, what is the benefit to you?
不同罢了
时间和精力要有具体数字。这“流程的一点点“就是你认为应该如何做的。
否则，事情与你无关。除非你是同事的管理，要对他做出来的工作负责。
题外的话：任何时候都不要在会上说别人不对。先肯定对方的意见：it's a good idea。（好不代表对，对不对，是另外一回事儿。）然后总结一下对方的意见的好处，最后提建议。
看到问题说出来没错，但是表达方式（激烈程度）可以根据结果的严重性调整。比如这次同事分析的有问题，老板帮着要喝，结果是多花了时间做可以简化的工作。这部分工作量如果不是问题，老板也无所谓，大张旗鼓的纠正就不会有市场。
此外我觉得简单明了的说清楚问题和利弊是种能力，可以把这个当锻炼机会。梳理清楚思路（领导有没有痛点），私下和领导解释，然后他自己决定。
弦外之音，这个同事比较强势，对自己不熟悉的部分冒充专家，对领导的影响力比较大。如果这个是不满的真正原因，那么你在这种被动竞争的关系中，目标是什么？这就是不同的问题了。
He can sense your attitude: you have a standard, which is not necessarily his. His trust in you is thus eroded. He cannot count on you to promote his agenda/interest. So he suggested you talk to him in private.
Your co-workers sense that too. So they don't have to take what you have to say seriously.
When you have a "standard" that is away from yourself, you may feel righteous that you adhere to a higher merit. But at the same time, you may have "lightened up" yourself by off-loading that burden onto some "ideal." As a result, you have made yourself a "light-weight."
If you say to yourself: I am the standard, and align that to your boss's, your office life would be more smooth-sailing.
沟通时也别直接说他的方法是错的，只说他的方法是所有可行性中的一种，还有其他方法，比如。。。
如果你不喜欢这个同事，就闭嘴什么都不说。错或是低效率是他的事，你事不关己，高高挂起就好了。
如果你要打击这个同事，才要私下到老板那里去说。我以为这是最不好的做法。
对同事，能团结就最好团结。当然如果这个同事人品特坏，没法团结，就绕着走，保持沉默，除非后果是产品失败。
求同存异吧。没必要伤害感情
仔细读了所有的帖子，首先是感谢，其次觉得这件事看来没有一个好的处理方法。要说明的是，这个同事就是浑水摸鱼，经常说一些错误的，不正确的，或者不严密的话，就是存在就是道理。这些问题不是只是做法不同，如果真是这样，我明白我不应该且没有必要提出来。
1. 在会上提出不好。因为老板已经说了，私下告诉他。因为这个同事一定会争辩，老板也搞不清楚，让老板做判断反而让他下不了台。
2. 私底下跟老板说或者email。我也试过，没有用，老板口头上说appreciate，但是，实际上，没有任何用。我猜老板心里也知道，但是他根本不care，他只care他自己。说多了，他还烦。
3. 剩下的就是不说，让他去。如果不说，长期下去，对我不公平，因为，他的很多观点根本是错的，错的观点我不说，反而让人觉得他的观点是对的，是good point。这样对我是不公平的。
4. 不说，不提，让他犯错。犯了错以后，他就胡乱解释，没有人知道，老板也信。老板不太懂，做错了，老板也不追究，而且，为了保护他自己，他也在众人面前替他解释，总能过关。
5。 我知道我不是老板，我不应该也不用我来worry about it。我想纠正这些问题，不是想打击他，也不是为了要credits，只是觉得这样是非不分真的是不对的，对我也是不公平。我们这一块，除了我就是他，还有老板。
我总结下来，觉得这件事是无解，这个地方就是一个没有bottom line 的地方。如果我不想走，只能忍。大家是不是觉得有同感？
这是一个关键点。因为他喜欢到处和别的组talk，然后就到我们组来一方面把别人的东西当做他的（虽然其实和我们组的东西没有直接联系），然后就讲自己的处理方法，很多都是错的，不完整的，或者牛头不对马嘴的东西。老板听作觉得很新鲜。我再纠正或者提出更好的，一直这样，我会发现老板觉得不爽，所以才建议我私下跟他说。
that your tone needs to change when talking to your boss, instead of just telling him what went wrong, can you somehow show to him that you have his best interest in mind, rather than showing how correct you are.
Do not sound frustrated, irritated, or contemptuous. Smile a business grin. Sometimes, a hint to the problem is enough. If that piques his interest, you continue, otherwise stop.
Whether he adopts your idea, that's his problem. You've done your part.
Came across it this morning, a good reminder:
"You will never have a greater or lesser dominion than that over yourself...the height of a man's success is gauged by his self-mastery; the depth of his failure by his self-abandonment... He who cannot establish dominion over himself will have no dominion over others." -- Leonardo da Vinci
作为同事，这种浮夸争功的人很讨厌，恨不得纠正他所有的错误，让老板“辨忠奸”。
但是从部门或者老板的角度看，可能重点就不同。如果浮夸同事所说的无伤大雅，没必要为小事计较，显得没气度。但如果会对你们的任务有严重影响，你应该escalate，对事不对人的说，从impact的角度入手，有你的分析和解决方案。
从你的帖子看，感觉你有take things personal的倾向。可能老板觉得你情绪上和这个同事不对付，所以不希望你们在公开场合掐。
简单的说，就是站高一点，从老板或者部门利益的角度看问题，不必为小事闹心。每个人都有优缺点，目标是为公司获利。