I'll be showing my bias here, but you're probably referring to NICE-SUGAR, which I think suffered mainly from having a pretty uninspired control algorithm. We built and simulated it and several other clinical protocols and it had the widest spread of performance, but it lost a ton of points to hypoglycemia performance, which is where you get into increasing mortality. The NICE-SUGAR protocol [1] has no notion of weight based dosing, and even has some completely missed edge cases. There have been similar studies in Japan with a better algorithm and they showed the expected benefits.

[1] - https://www.glycemiccontrol.net/NICE/StudyDesign/NiceALGORIT...