Since when does retconning have to do with knowing the rules? If you don't know the rules and have to do things over because of it, I feel for your players.
Generally, retcons are requested because the player believes that he understands the situation better than the DM does or that the DM didn't make something important clear.
The first type occurs when players say, 'but I didn't go straight when I walked into the room', 'but I only took one step into the room', after saying something vague like 'I walk carefully into the room'. If carefully means 'left along the wall' or 'only one step into the room' or 'probing ahead with my 10' pole' then you better say it before hand (in some fashion) and not afterwords, because in my experience if you start letting players define actions after they occur the action will _always_ be the most appropriate for the knowledge they gained from trying the vague action. One of my favorites is 'I begin searching the room'. If you say this to me then I assume the right to place a random character (indeed every searching character) randomly in the room on the grounds that if there is treasure to be found in the room _anywhere_, the PC's expect to find it with a search roll. PC's never complain when I say 'Bob, in the dresser you find a sack of gold coins.' But there is no end of complaining when the random thing to be found is harmful, 'My character would have never gone near the dresser!' or 'My character would never be more than 5' from Bob's character.'
Well, you should have said that at some point before you said 'I search the room.'
The same sort of player is usually the type that gets ticked when I make search and spot check in secret, because they are used to metagaming the result (gee, under 20, I must have failed, better search again until I get a good roll).
Comparatively speaking, those aren't so bad. What gets really bad is the 'You didn't make clear to me that the results of this would be bad for me so I want to start over', or 'I didn't understand that rule, and if I did I would have done it differently', or 'If you told me that the slime on the wall in room 15 was purple to begin with...'. If someone does this, they usually don't want to go back 1 action (which is doable so long as it doesn't have any real consequence), but 5 or 20 which grinds play to a halt. I've seen DM's wheedled to death with this sort of thing.
Third edition makes clarity so much easier because I can define how much information I give out based on dice rolls in a fair and just manner (ok, wilderness lore check (DC 10) failed/succeeded, so, 'Bob, you recognize the slime as...')
I should make a few things clear. I do overturn myself occasionally. I can't imagine a DM that can keep track of everything. I don't consider that retconning. Sometimes I forget a PC has a certain special ability, a spell up, or some other matter. Generally this sort of thing gets caught almost immediately by the player(especially when serious damage is involved) and generally it almost always involves bookkeeping like how many h.p. the PC has left, how many potions the PC has left, how much xp got awarded, etc. I'm perfectly content to come back in 5 sec., or 10 min. or even the next day and say, I've been thinking and I think I ruled X bad, or I forgot Y, and so Bob gets 13 more h.p. or John gets a potion of extra healing back, or whatever. Still everything about the session _happened_ (sans maybe the consumption of a potion). The clock doesn't get rewound. I've never felt the need to say 'Your character is back, 'Poof'. (fortunately) If I really felt bad about a ruling, I'd probably have deus ex machina come save the day rather than retcon or replay anything. Once an action has resulted in OOC or IC knowledge of the universe that the PC didn't have before the action, IT HAPPENED (even if it was according to my notes wrong) and the universe (my notes) reforms to take that into account. The things I'm likely to forget are just as likely to help PC's as hurt them.
Players never ask me to retcon things that make things easier for them.
Most often if I'm forgetting something, a decent player can remind me before any consequences are applied.
As a player myself, I try to abide by the rules I set for my players. I've even been known to remind DM's of circumstances that have caused my PC to take damage. Players that think of the game as the PC's vs. the DM tend to look at me like I'm nuts when I do that.
PS: BTW, as a DM, I don't 'think' I have authority. I have authority. It's my game, it's my table, and it's my notes that 40 hours of my life were poured into. You don't like it, find someone that enjoys having you at his or her table or run your own. And I feel the same way about any other DM that takes me on as a player. _Their_ game. _Their_ rules. _Thier_ world. _Thier_ preferences. They are in charge.