Ever tried putting plywood under them? It stops the sinking and is way more stable. Home stores will even cut it to size for you.

Wait, your yoga teacher actually talks about months? Mine acts like you should be doing perfect handstands by week two. People want instant results, like those weird juice cleanses that make you faint. But she's right, I guess. Holding a pose for five more seconds this week does add up. Still sounds suspiciously patient for a fitness person.

Dovetail joints for a desk? That's wild, man. Most people start with boxes.