World of Tanks is not a MMORPG in any classical sense of the term. Nevertheless the game does have a "game of advancement" part, which can be compared to the game of advancement in MMORPGs. Thus today I would like to discuss the experience point system in World of Tanks.
Experience points in World of Tanks are used in the tech tree to research new equipment for your existing tanks, and to unlock the next tier of tanks. You play your battles, and you get experience points based on your performance, including factors of what you scouted, how much damage you did, and how much you participated to capture the flag. There are small bonuses for things like kills, but actually taking the last percent of health from a tank somebody else damaged doesn't give all that many points.
The experience points you earn are for the largest part linked to the tank you fought the battle with. Only a small portion is transferred to a separate count, "free xp", which can be used for any tank. Thus if you play a tank which is already at elite status, that is has all the possible technologies already unlocked, or if you play a "gold" tank which is outside the tech tree, most of the experience points from the battle are not useable at first. But there is a button to "convert" experience, which transforms the xp from tanks where it isn't useful any more to free experience, for a fee paid in gold, that is real money.
Now this system has advantages and disadvantages. The advantage is that you aren't forced to play the tank you want to advance with. Free experience is especially useful when you get a new tank, with no advanced equipment, and you use the free experience to upgrade that new tank right away, without being forced to play it in a severely underpowered form. But of course it is also useful if you are playing your favorite "old" tank, or farm money with a "gold" tank, where converting enables you not to simply lose the xp. The disadvantage is that the conversion costs real money, about 0.01 cent per point of xp converted. That starts out being relatively cheap in the lower tiers, but once the xp costs reach the hundreds of thousands, that gets expensive quickly.
Apart from the cost aspect, I find the idea to play one "character" to advance another interesting. Usually in MMORPGs that sort of "twinking" only works with the transfer of virtual currency and items, not experience points and levels. Thus I was wondering whether this wouldn't be a possible solution for example for World of Warcraft, where the players interested in the leveling game find progress too fast these days, while the people leveling an alt only for the endgame find progress always too slow. What if your level-capped main would continue earning experience points for his various dungeons and raids, which he could then transfer to an alt at some sort of exchange rate? This would allow to make the normal leveling process slower, giving casual players enough time to explore the zones, and would give players interested in leveling an alt quickly a means to do so. What do you think?