> If not, is there an easy way to get 90-95% of the way there?

**Use `bs=1M`**

It'll give you more than 96.3% optimal performance over more than 87% your devices, from slow USB2/3 flash drives, SD cards and hard-drives to fast NVMe Gen3 SSDs and even RAM-only devices such as `/dev/zero`.

Source?

Voices in my head.

And some empirical testing over 10+ years using `dd` combined with pseudo-scientific benchmarking and biased common sense.

Hey, you asked about the _easy_ way!

Jokes aside, `bs=1M` is a good, solid, no-brainer, trouble-free go-to generic default if you can't or don't care about fine-tuning for a specific scenario or device.