I believe Ethereum price action to be independent of Bitcoin's value.
I strongly don't think so. Bitcoin is the daddy and command 60% dominance, traders will always flock to the coin with the most liquidity. But in a bull market, traders spread out as the markets expand.
But it should be understood that this may be just one of the corrections in the downtrend vs BTC.
Could be. That's why the arrowed line stops around 0.03btc.