Disregard this, I figured it out. Was expecting the "long_desc_key" to change to something like "long_desc" like on the quest xml. Turns out if I just replace the key text with my message it will use that instead.
Stock
<effect_description level="4" desc_key="perkCharismaticNatureRank4Desc" long_desc_key="perkCharismaticNatureRank4LongDesc"/>
edited
<effect_description level="4" desc_key="perkCharismaticNatureRank4Desc" long_desc_key="Your leadership abilities are top shelf, allies can jump 50ft higher, shoot lasers out of their eyes, and cure cancer using a paperclip and some duct tape."/>
