The notion of a medieval knight in his full war panoply is surely intimidating, but the gilded patterns and the ostentatious accouterments in his armor (especially after 13th century AD) were probably not demonstrated in actual battles. In other words, the medieval knight wore a more practical variant of his armor in combat scenarios, while the ritzy stuff was kept aside only to be showed off in parades and tournaments. This doesn’t necessarily mean that ‘ordinary’ war armor was any less valuable or significant. Such monetary values were also complemented by advancements in technologies that enabled knights and well-armored soldiers to have some degree of mobility combined with safety. To that end, contrary to popular notions, plate armor usually tended to less cumbersome than their mail counterparts, since the distribution of weight in the former was far more streamlined.
Interestingly, as jousting became more renowned as a dedicated spectator event, specific armors were designed in the middle ages for such activities. One particular example from early 13th century aptly showcases the extent of modifications being integrated on the medieval knight armor system. – including the incorporation of larger pauldrons reinforced by extended gardbrace, and the massive ‘frog-mouthed’ helmet with a singular eye-slit.