Has it got to do with common sense?

Yes, if it regards to how many legs can or should a dining table have?

Generalised Feng shui originated from this common sense. This is why most geomancers felt that dining tables should have four legs.

This illustration seems to suggest that if one leans at the edge of the table, will the table topple down?

In normal circumstances, if a table has four legs at each corner of the edge, common sense says that no way such a table can tip or topple down.

Please look at the illustration, below. If quality materials and good structural integrity is there, this table should hold it's weight:-

However, there is the concern of wear and tear; plus it may have a weight limit. "Better safe than sorry applies".

Case Study: Is this type of dining table okay? Client is concered with the corner of a dining table... but to me.. it is more than just this concern.

Hi Master Lee,

Client: Don't mind just a quick check with you. Can a corner of a table be considered a form of poison arrow?

Reply: More to do with common sense. Especially if there are small children running around. Often have to later on place a child safety plastic corner pad.

Since living room sofa is not close to this is okay

This not so small children friendly that’s all.

Reply: More importantly, please look at the type of legs for the table.

Reply: For this table: "If a child climbs on TOP of table (as shown below); will this table TOP topple down?"

Client: Thanks master Lee. Makes a lot of sense
Client: Ok ok.
Client: Will look for something that is much harder to topple.

Reply: Yes function vs stylish

Client: Safety first
Client: Once again thanks for your advice

Reply: Frankly, a lot of Feng Shui is pure common sense