Alright,
We should assume the the market is going to go up, right? Otherwise we wouldn't be in it, yes? So, While the ETH USD rises over the BTC USD we could assume that BTC USD is also rising but not as much as ETH USD, so when going back to BTC from ETH it would be (overtime) more than it was when you had started investing 1. because you beat the market and earned more using ETH and 2. Because the BTC price (and whole crypto market cap went up as a whole). I enjoyed your post.