If done right yes it worth it. Start at 20mcg. and increased like you've said. You'll certainly drop to 7% fast enough. taurine potassium always. if you want to keep the dose as low as possible you can take keto even in a 2weeks on/off. IMHO it wont be a waste. But it will certainly not be at its full potentiel. so that's your call.
Drink PLENTY of water btw...
Good luck