However, I would like to note the distinction between a system in which you can do romance plots, and a system that actually has a mechanic for the romance itself. I don't think anyone who wants to roleplay romance will at all be satisfied by "Roll a die, check the chart... and Yes! He accepts your token for the joust!"
My experience says otherwise. I know D&D has sort of enshrined this idea, but in my experience, I've found it to be a complete myth.
The base idea of mechanics for romance is not a bad idea, any more than the base idea of mechanics for combat is a bad idea. They're both conflicts, they both involve conflict resolution, and there should be some way that the player's character can influence the resolution of that conflict.
The key to it is having player input. If the player has unique and special romantic abilities that can be used to overcome that challenge -- and if the game rewards those romantic pursuits (in the form of XP, or treasure, or whatever) -- it can be as involved and interesting as a fight.
One thing I'm sure no player really wants to do is just constantly ask the DM "Can I do this?", or to resolve something important with a single die roll that everyone has an even chance on.
It would be like running combat based on your descriptions of your attacks, or on rolling a d20 and having anyone who rolled below a 10 die. It's not very satisfying.
Add diversity. Add player input. Add the elements of
rising action (and reward) to this conflict resolution, and you'll find that people are into playing a game that lets them fall in love as much as they are into playing a game that lets them kill monsters.
Mechanics are at the core of the experience. Without robust mechanical support, you've got random chance or DM fiat, neither of which encourage much player input by themselves.
Some people might not want it; some people might WANT a game where their own powers of talking help them talk to NPC's, just as some players prefer a game where their own powers of puzzle-solving help them solve puzzles, and their own powers of sword-fighting help them sword-fight.
Sorry if it sounds like kind of a rant, but the idea that "you don't need mechanics for role-playing" is pretty deeply ingrained in the D&D community, though it doesn't seem to apply to the broader table top RPG community at all, and the point is one I've argued kind of a lot.
