This letter revisits the equal-gain (EG) spatial diversity technique, which was proposed to combat the human-induced shadowing for 60 GHz wireless local area network, under a more practical frequency-selective multi-input multi-output channel. Subsequently, a suboptimal spatial diversity scheme called maximal selection (MS) is proposed by tracing the shadowing process, owing to a considerably high data rate. Comparisons show that MS outperforms EG in terms of link margin and saves computation complexity.