Most billiards halls sport a one-piece slate table. With all the players leaning and climbing onto it, the single piece most effectively withstands the weight and keeps from losing alignment or leveling. At 450 pounds, the slate is incredibly sturdy. Over time, though, that weight may cause it to sag or warp, and these gentle valleys formed in the stone become impossible to buff.
For the average homeowner, the stability of the one-piece slate is actually one of its biggest downsides. Most movers hate the slate because it’s heavy, long and unbendable. This makes it difficult (sometimes impossible) to navigate around corners, stairs and doorways. In fact, maintenance for a one-piece table is more expensive.
Alternatively, the three-piece slate can be transported and setup without hassle. More importantly, the person leveling the table actually gets greater control because each piece can be adjusted individually to accommodate unevenness in the flooring and in the slate. This translates into more precision leveling. The smaller centre of mass in each piece also prevents issues with warping.