In what way? Certain legendaries are overused for a reason. They have no particular advantage over a regular Pocket Monster. Heatran, Azelf, etc. All very useful, yet you could say the exact same for Salamence, Lucario & Gengar. Heck, some of the top Pocket Monsters in the game are regular Pocket Monsters, usage wise. The reason I despise the rule is without the balancing effect of legendaries, the overused metagame shifts a bit in my opinion. Not to mention it takes away prediction and certain worries.
Think of it this way. You're in a battle and your Lucario is in, and you see a Cresselia. Now you don't have to worry about one of Lucario's main check downs, Choice Scarf Heatran. While in another OU match, you still have that Heatran in the back of your mind. Maybe it's easier, but some players thrive off of uncertainty. (I know I do)
Frankly, while legendaries are helpful, they don't have an advantage over any other overused Pocket Monster in my eyes. I'm not saying you have to change your rule, and by all means, if your competitors like it that why, all the more to 'um. And maybe I'm just biased. Seeing as all of my teams have multiple legendaries, haha. Just voicing my opinion, I guess.
And Florida's good, still sunny as always. XD