Brunswick adapted pool tables in 1845 from English billiards tables (snooker came much later). Smaller tables and easier pockets made it all more approachable for non-devotees. Also, they would fit homes and public spaces - bars - more easily.
Slate has been held in place the same way for about 150 years - wood screws into wood with shims of playing cards or business cards ever since. Okay, plastic tapers with teeth are a small improvement. Is there anything more important than the level of the table?
Around the year 2000, after twenty years in the biz, I saw a photo of how Billares Sam dealt with the problem of KEEPING it flat - thirty-eight MACHINE SCREWS into a steel frame holding the slate up or down. I presumed it was a German idea, but no, Spain made the first real improvement in tables.
I bought a 9’ KimSteel (now KSteel) when we moved the room to the centre of town in 2007. We moved it elsewhere in the room three years later and it was still perfectly level. Not 1/500th of an inch per foot out anywhere. Heaven. So four re-clothings and we had to re-shim or re-bondo at all. Saved, say $30 each time. But what matters is that players could count on it. No practice slow shots by the rails to test it necessary. Sold a few too - my enthusiasm was catching.
In 2018 I got a 9’ Rasson Victory 2+ which has 22 devices which double-bolt into an aluminum extrusion that sits on the sturdy frame. The devices adjusts the slate until you have it exactly right, then you machine bolt & lock-nut it tight. Each one holds the slate both up and down. Peacock Billiards now has 4/9’s and one 12’ Rasson (which has heated slate and these fabulous devices). None go out of level with the - call it ‘untutored’ - public enjoying them thoughtlessly.
My two Unik 9’ tables stay flat also - they each weigh 2,000 pounds. Those are a story unto themselves.
I won’t get PLAYERS' table again with wood screws, ever.