RG,
Regarding good English, the "pedants" here aren't the issue. The issue, whether you like it or not, will be how poor English might be viewed by those that could influence your career.
Don't think for a minute that plenty of people won't notice incorrect grammar or spelling; when they do, it will affect their impression of you. Most people won't notice good grammar, but they will understand your meaning more easily, making you a more effective communicator.
Good luck with your career. Do well and be happy.