Sephiron wrote:If you're really good at minesweeper, you don't even need mining supports lol
Occasionally you'll hit a 'wall' of tiles you can't confirm to be safe, which requires a support (unless you want to dig all the way around it). There's also no safe way to dig out cave walls (and if it has dust your next tile is simply a random guess).
Once you have your first metal, it's always more efficient and more convenient to just build mine supports for ore mining. Even just the additional yield from unsafe tiles more than makes up for the cost of the support.