Here's the scenario:
1. Buy BTC and ETH on CB with USD, hold them.
2. Months later, buy BTC/ETH, transfer to another exchange (Bittrex/Binance) and immediately buy an altcoin and hold.

So (1) isn't a taxable event because I never sold them (unless I'm forced to use FIFO reporting, then it gets murky - but my lots are very clear/specific).

(2) apparently is taxable, but since I did the entire transaction within an hour, do I still need to report it? The gain/loss would be tiny since the entire lot transaction was done within an hour (usually less).