The autothrottle was agreed very accurate. Interestingly enough, though, many of us got used to using the total fuel flow meter to gauge power settings for the approach. I can't remember the figures with the passage of time, but it went something like, at glide slope intercept, reduce total fuel flow by 100 lbs/min...
It made flying circuits very much easier with just a glance at the meter as opposed to fiddling about with rpm settings [of course, for accuracy, you tweeked the individual engines to line up rpms around the right total fuel flow figure].
And yes, a 90KIAS approach would induce an almighty high pucker factor!!!!!