Using \displaystyle at the beginning of mathematical expressions enhances their visibility, particularly for larger equations. The discussion emphasizes that while single dollar sign delimiters are typically used for inline math, using \displaystyle can lead to larger fractions that may disrupt text flow or line spacing. To manage size, \tfrac can be employed for fractions when \displaystyle results in overly large expressions. The \dfrac command is recommended for displaying fractions clearly in larger formats. Overall, the conversation highlights the balance between clarity and aesthetics in mathematical notation, particularly when using display styles.