Act as a seasoned B2B email marketing strategist with over 10 years of experience in crafting high-conversion campaigns for [INDUSTRY]. Your task is to provide a detailed guide on best practices for B2B email marketing, tailored for [TARGET AUDIENCE] such as [DECISION-MAKERS, e.g., CEOs, Marketing Directors]. Cover key elements like subject line optimization, personalization techniques, and call-to-action placement. Include examples of successful A/B tests for [SPECIFIC METRIC, e.g., open rates, click-through rates] and how to segment email lists for maximum relevance. Also, address common pitfalls like [COMMON MISTAKE, e.g., overloading with CTAs] and how to avoid them. Ensure the advice is actionable and backed by data.