between what happens in literary accounts of tournaments and what actually happened.

Jousting was dangerous- I suspect the ever-real possibility that someone might get killed was part of the attraction for some spectators, a bit like motor racing today. Even kings, who presumably had access to the best equipment on offer, died in the lists; the most famous case would be Henri II of France, killed in a joust as late as 1559. The gratuitous dangers of jousting right from the early days in the 12th century (when tournaments might be fought out over a wide area of countryside and looked very like straightforward warfare) meant that it was viewed with considerable concern by the church. There are 12th century stories about men who had died in tournaments coming back from Hell to warn their former comrades of the spritual dangers of participating in such activities. While this hostility changed a bit over time under social pressure from the great (who didn't fancy the idea of, say, a king's son being refused burial in consecrated ground because he was a tournament fighter who'd been killed in one), it never quite went away.

In principle, however, you weren't supposed to be killed in a tournament. Tournament organisation became much more structured in ways which limited some of the risks. Armour got heavier (and a lot of the spendid suits of armour in modern museum collections are actually tilt armour, not the armour that their owners would have worn in battle), saddles got higher and higher so that by the end of the 15th century it was actually quite hard to knock your opponent clean out of the saddle and an increasingly complex scoring system evolved in which, for instance, a hit to the helmet counted for more points than one on the body. Breaking a lance in the approved manner also counted for points (ironically this probably made things more dangerous in some ways- Henri II was killed by a splinter from his opponent's lance which came though the eye slits of his helmet). I remember many years ago seeing a "score card" from an English tournment in Henry VIII's reign which was used to work out who'd won a set of confrontations between individual knights- I suspect there were jousting statistics bores in the late middle ages who could tell you a given knight's average score per course like the statistics freaks who follow cricket or baseball more for the statistics they generate than for the pleasure of the game *s*.

Of course you were supposed to be fighting for a lady and wear her favours, though this could easily turn into a bit of a superficial pose. Certainly very few ladies would seriously expected the man who wore their favour to get himself killed on their behalf in a joust (and any knight who encountered one who did would have been well advised to transfer his favours elsewhere).

There is of course an exception to this- judicial combats. There were never as common as Hollywood might suggest and had become extremely rare by the 14th century. When they did happen, however, they tended to be fought to the death. There's been a book published recently called "The Last Duel" by Eric Jager which tells the story of the last judicial combat in Paris in the 1380's; I'd hesitate to recommend it too much as it's not a very good book in many ways but it does have a very gruesome climax for those who like that sort of thing.