If you plan on switching jobs every time rewriting someones code over the weekend and demoing it to their boss results in bad things then you better keep your resume polished.
No, but if people get pissed at you for working overtime to dramatically improve the system, it's a strong sign there's a better place you could be. Could the guy be more tactful? Definitely. Could this be the best place the guy could work? Doubtful, if he could make such an impact. But being ostracized rather than educated indicates an unhealthy work environment.
