Lichess Opening Explorer. Must have feature.

#40 An opening book is a must for atomic games or you will not last 10 turns as black...believe me. The difference is just in rated real-time games you must remember the book while in unrated and correspondence games you can view it. I personally find both book-allowing (aka book-reading) and book-disallowing (aka book-remembering) games useful and my final goal is to completely remember the book.

I am not talking about atomic I am talking about regular correspondence. For atomic I cannot comment as I do not play it.

#42 I do believe books should be allowed for atomic and three-check, not necessarily for normal chess and other games.

BTW atomic is fun but you should first play unrated correspondence games using books before playing your first rated game or you will be beaten insanely hard..like you can lose your first game in 3 turns if you are clueless about it. I still frequently lose games as black to 2000+ players in less than 10 turns due to the fact that I do not remember the book. (Yes as white I at least generally last way longer)

I disagree with the above point about cheating in CC. As thibault said, if people really want they can cheat anyway. But in an unrated CC game it is a useful feature (you can agree with your opponent on using book) since CC played mostly to improve ones chess and there a book makes a lot of sense.
One important feature IMO would be how well people performed rating wise in those lines. 60% means not that much if the white players had on average 50 rating points more than their opponents.

@hauteepoque said earlier "now that the database is available, lichess can/should do away with available fen and pgn strings in analysis, which were useful to export into outside databases but not useful anymore, ...or I don't see the necessity maybe"

I use FEN and PGN export every day for analyzing my games in Stockfish and in tools that I am developing myself. Disallowing the ability to export would go against the spirit of openness that (in my opinion) defines lichess.

@dsjoerg. I understand that. But don't you use fen and pgn only once the game is over ? I suggested (in my second post maybe) that they be made available precisely then, at the end of the game, for players who want more than the lichess analysis.

I see well that people who want to cheat will cheat anyway, but giving that as an explanation to why lichess maintains fen and pgn available in the course of the game seems a bit odd to me... I thought there might be a practical reason to having the strings on the screen which I had not thought of.
Are they there for exterior players wishing to engine-analyze the game as it develops?

I use books and databases in cc, and I don't consider that cheating at all, cc is about learning, and in the old times when cc moves were sent by post, players used their time looking for similar games in books and magazines, (probably) discussing moves with fellow players, etc. Research is at the heart of cc. Ultimately, the decision to make a specific move is personal.
Using machines is different because the effort and thinking is lost, and unfair to the opponent who might be relying on his own human research only.
Therefore, I believe using books and a database to understand variations is part of cc. Offering the database on the game page is a comfort to cc players.
Therefore I do not understand posts about not allowing this feature to be used in correspondence. I would gave thought the opposite: using research tools is illegal in otb, not in cc. Why should the use of this feature be restricted from cc games and not from classical say 30 minute games where players have the time to consult it while playing ?

In correspondence I would even insist on my opponents to use books and databases, analyze their findings and come up with improvements if possible. The whole point of non competitive correspondence is to get your openings in shape for OTB play (for me, at least), and that requires maximum resistance.

I propose that for CC games (including variants rated, or not-rated), the limits to outside help should be removed. Allow everything, including but not limited to opening books, game databases, use of computer chess engines, use of EGTB - endgame tablebases.

CC is about finding the truth in a position, finding the best move. By this the idea of cheating allegations will also cease to exist.

Disagree with the last post. It is not fun to play with engine help in correspondence, as it kills any creativity.
If you wish you can use it in casual games, but you must have an agreement with your opponent before the game.

However, I think that opening explorer should be allowed in correspondence. Because it will lead to more quality and interesting games, improve player's opening knowledge, encourage to observing master's games and learning.