optimizing my 忘 retention loop (currently at 68.4%)

Okay so my 忘 retention fell below my target 85% threshold this week. To fix this without burning out, I started a strict micro-drill protocol. Phase one is a 90-second sprint looking at 忘 every hour. Phase two is writing it 15 times next to 五 and 志望 just to anchor the radical. If I drop below 70% again I'm doing a 300-minute lock-in session. Anyone else tracking micro-intervals for this or am I over-optimizing?