Quuestion about adding a CVAR value to a buff

[Skullfracture]

So I'm trying to merge several custom food mods (one of which hasn't been updated since a17) and I need some help on how this would work.

The original is:

            <stack_type value="duration"/>
            <duration value="300"/>
            <effect_group>
                <passive_effect name="HealthChangeOT"         operation="base_add" value="0.233" />
                <passive_effect name="HealthMaxModifierOT"     operation="base_set" value="0.233" />
            </effect_group>

I would like to replace the HealthMaxModifierOT with $critHitNaturalHealingRate but the only reference to it I can find is in the Natural Healing perk as a cvar. Will this work?

            <stack_type value="duration"/>
            <duration value="300"/>
            <effect_group>
                <passive_effect name="HealthChangeOT"         operation="base_add" value="0.233" />
            <triggered_effect trigger="onSelfBuffUpdate" action="ModifyCVar" cvar="$critHitNaturalHealingRate" operation="set" value="1.5">
                <requirement name="HasBuff" progression_name="buffname" operation="LT" value="1"/></triggered_effect>
            </effect_group>

Any advice appreciated.