However I can _quite easily_ see how a non-native English speaker could use the phrase “if you know what you are doing” to mean “if you are careful”.
He just replaced "cannot consistently synchronize data" with "cannot consistently deploy a system that can consistently synchronize data". But what's the difference between those statements to people that need to solve that problem? None.
But obviously it is a tactic of the doomed.
This kind of thing is a scourge. I had a Chinese friend respond to something I said once by saying "that's nice". It looks so innocent... but it's really hard to overlook the fact that "that's nice" is a serious insult coming from a native speaker. I had to ask them to please never use that phrase to me again.
To my ear (American who grew up in the South, lives in the Midwest, and works with people largely from the Mountain West), "that's nice" could definitely be used dismissively or sarcastically, but there's any number of ways to say it that are actually sincere and genuine, and I can't imagine a situation in which it would be a "serious insult".
I mean, I can imagine that in a professional setting, if the coworker was saying it with a sarcastic tone or being showily bored or dismissive when saying it, that their behavior might be insulting. But anything can be insulting if it's delivered in an insulting way. "That's nice" has no particular edge to it to my ear.
So I have to assume you aren't American, or that this is a regional thing that I don't have experience with. In any case, your reaction to "that's nice" reminds me of an American friend of mine who moved to London and when her coworkers would ask her if she had a preference about where to get lunch, she would reply "I don't care", which would be totally normal (to me) in the US. But to her British colleagues, that word choice made it a very rude thing to say (the appropriate reply being "I don't mind" to indicate that she didn't have a preference and was willing to go anywhere).
