TL;DR - A different approach calculating strength based on Donchain channels
My approach calculating strength by using the difference between price and donchain average. It is possible to use the highest/lowest value of a given source (like close) or to use the highest high/lowest low (by using the option 'include wicks') for the strength calculation
I added...
RSI Donchian Channels
Built by Ricardo and JR
Here is a great indicator to use for strong trends. Donchian Channels react immediately to changes in the highest high and lowest low. For strong trends you want to trade when RSI is set along the upper or lower DC-RSI envelope. When the RSI releases from the DC-RSI envelope, you can take the trade off.