This paper presents Sarawak Shell Berhad’s journey to explore inspection techniques to better predict corrosion growth rate of a 32inch High Pressure and High Temperature pipeline suffering from Top of Line corrosion. The main challenge to the inspection is accurately measuring more than 200,000 internal corrosion anomalies, 96% of which are categorized as pinhole. Compounding to the problem are high wall thicknesses, asymmetrical wall geometry and ever-changing operational condition. Since first gas in 2006, the pipeline was inspected a total of 8 times using Magnetic Flux Leakage (MFL), Acoustic Resonance Testing (ART), Eddy Current, diver-operated spot ultrasonic testing (UT), ROV-operated UT scan and Time of Flight Diffraction (TOFD). Inaccurate pinhole measurements means that the corrosion growth assessments were conservative, and the pipeline predicted failure was imminent. The pipeline was planned for sectional replacement across 24km, while structural clamp was planned as a temporary measure to extend the life at key strategic locations. This paper will detail out how repeatability, and not accuracy was key to reduce conservatism in corrosion growth assessment among pinhole anomalies. Additionally, this paper will discuss how deep collaboration between operator and technology providers resulted in increased confidence in data quality, enabling operator to milk out every valuable meaning out of data collected over the years.