Asceticism & Player Stun Threshold (PST)

The Notable "Asceticism' changes the PST value to be based off 30% of their (Maximum?) Energy Shield instead of Life. The updated tooltip says that, by default, base PST is equal to 100% of their Maximum Life.

In other words: one needs their ES to be more than triple their Maximum Life in order to get a benefit from this Notable.

That seems a little ridiculous. I understand the primary users of this are Chaos Inoculation builds, but I'm a bit disappointed that my Ghostwrithe-using Acolyte of Chayula actually loses PST when allocating this passive.

While wearing Ghostwrithe, he has a little over 900 Life and 2800ES. This just means that I have to invest even more points/gear into ES (to push my shield over 3000) in order for Asceticism to be worth allocating.