Source: http://www.rpgamer.com/games/sd/som/reviews/somrdrev6.html
Quote I found interesting
"a command gauge refills after about two seconds to 100%, in which case the weapon's strength will be normal. The player *can* button-mash to fight enemies, although doing so is a terrible idea, because if characters don't wait for their gauges to fill up to 100% first, their attacks will be much weaker."
Also, the gauge will decrease if defending. There is no way of blocking in SoM so yea.
While I will not go to the link, I am familiar enough with the attack system in Seiken Densetsu 2 to know where you are going with this. And I think that I would agree with this only from a personal perspective seeing as I am not certain if others would be down with this.
So if we are regarding the gauge then it must have different applications for each type of weapons if all weapons are to be effected. Let's say for instance, swords act as you have just said. The entire sword combination ought to occupy the supply of that gauge. In this case, the bombs should consume all of it. The same concept would apply to guns in terms of aim. If the gauge is empty while shots are fired, most of the gun's shots would slightly deviate from their target, in a fashion more noticeable than the Blaster's variants; not all of them hit the same spot with consecutive shots as I have seen.
For shields, defending should always be possible. But with each bit of the shield's health chipped away (as indicated by the gauge), the gauge itself ought to be depleted as well, leaving less available strength for a counter. Shield bash ought to consume half of the gauge health as it was made to do. And similar to the bomb's consumption, all charges must use all of the gauge once the attack is administered. The command gauge should not reset upon switching weapons (for whatever reason one would implement that). And lastly, let dash remain with its 8 second cool-down.
While I would also say to either reduce that cool down by a slight or initiate factors that could affect your gauge's consumption, the idea looks like it may take more work than some would know and upset a great number of people.
Because I do not know how well this would mesh with the community's style of play (for those few who voice their opinions in the forum), you have some of my support for this idea.