Spread designs could be a really strong base when made well. It aims to protect against the two main threats when fighting against players with unlimited resources on the world map. PPX and multiple Twig/Pebble catapults in the millions. Spread designs give up on a very strong defense and instead aim to force the enemy to make many attacks to trigger damage protection. The design forces attackers to make more attacks, and it can end the attacks when it triggers the damage protection. The example is the Spark 3V and is a favourite for fighting against large empires.
Spread designs are an excellent defense for players that log on frequently. The pathing on this base design has been extremely well tuned and falls in the category of anti-ppx. ADTs are designed to be destroyed after all the other towers have fallen. The pathing is resistant to multiple attacks and the extra range of Daves. Due to the advanced pathing the design generates moderate firepower against attackers. Spread designs are optimised for world map where you are fighting a strong player placing overwhelming force on you.
Spread bases require high yardage upgrades, which cost shiny, this means they are often out of the reach of many players. While, it is difficult to destroy well made spread designs in a few attacks, the weakness is that they are easy to damage a little bit at a time. The design can be cheaply worn down with multiple weak attacks and this tactic can be successful if the defending player does not log in regularly enough to repair.