Movements are slower and more tactical. Technique is at the forefront. Due to clothing, more movement options such as grips are available to block the opponent’s movement.
Also in gi form, size and power differences affect your performance less. So, a short small old person can easily take down a younger and larger opponent if he has enough experience and skill.
Gi training is a great option to perfect your moves and advance your game with technical strategies.In gi training, unlike no-gi training, it is not pure physical strength that matters, but how good your technique is.