Less than 150ft on a go-around from a PFL? Interesting...
Why? You're not suggesting that you should never fly below 500' AGL during PFL training, are you?
Whilst this may not be an approved method, the one thing I find with PFL training is that there is a tendency to panic over doing the drills so for the first demo (on the way home from an unrelated lesson) I get the student to relax and start the stopwatch when the engine 'fails' at 2,000' AGL. Trim the a/c for Vg and simply time it down to the ground (or as near as). Then, in the safety of terra firma, go through the drills in the cockpit at an easy pace and time them. I find it helps to build confidence when they see that there is sufficient time to carry out the drills in the air.