This is a debate that cropped up in my group in the past few weeks. When we award experience, are we rewarding the player or the character? The DM took the stance that for XP goes to the character. This seems rather logical and the alternative, of rewarding players for their actions rather than the specific characters, may seem odd but bear with me for a moment.
XP is not a thing that exists in the world of the game. It is an abstract method of reward for the character completing certain tasks. While the character would explain any growth a result of some period of risk, training, or research, none of those tasks are completed unless the player wills their character to do it. To argue otherwise creates an artificial separation between the player and their character.
This may not seem like a problem, but the second you introduce a dream-based adventure or give the players alts to use for a scene the question rears its head: do we award XP for this? If we're talking about reality, that is, how things function in the real world, why should I give XP for playing out a dream based adventure or for someone else's experiences? For these questions, I have a simple answer: because gaming time is limited. If you ask the players to roll dice, they should be rewarded experience. Otherwise, those scenes should only exist as narrative pieces.