I'm going to leave this game even cost me a lot if you keep the stupid MARK spell.

Here's the thing, though. Mark/Dash has a ridiculous range, and I wouldn't doubt a lucky shot could clear the entire gap between the first two turrets, so long as they land the Mark. Now, on top of that, compositions with high-damaging champions like Lee Sin, Master Yi, etc. or champions with high damage up-close like Darius or Karthus can literally ignore the range factor that makes putting their abilities to use a challenge. And when those champions lose the challenge of applying their abilities correctly, the early game, often the deciding factor of most matches winds up with an array of snowballs and an ace within the first three minutes. Even if one team is exclusively ranged champions and the other exclusively melee, Mark/Dash throws the scale far off-center by allowing already mobile hard-hitters to press too hard on the assault, making the not-so-mobile and not-so-tanky ranged champions suffer a strict disadvantage. So, while, yes, it is doing its intended job of making melee champions more capable of initiating things, it also makes it difficult to retaliate when players get overwhelmed from across huge gaps and can't recover. So, I agree with the OP, and I'm giving reasons in their defense.