Use 'in the extreme' to highlight extremely intense qualities or behaviors. His dedication to his job is punctual in the extreme.
Pro Tip 2/3
Negative Connotation
The phrase often suggests a quality has moved beyond normal to potentially negative. Her frugality is economical in the extreme, bordering on stinginess.
Pro Tip 3/3
Subtle Critique
Can imply that an extreme degree of something may not be entirely positive. His approach to problem-solving is cautious in the extreme.