I'm afraid that databases and books that you use are better than the free versions I can access, so let's prohibit them and treat it like an OTB game like BJJ prefers. (I don't think it will make a huge difference - I'd be choosing sidelines anyway ) You're however allowed to examine my past games (as well as any other sources) before you start this one, as it's legal in OTB chess too. (Edit: strictly speaking, let's also prohibit using an analysis board, though I see no remotely easy way to check if either of us is using it. I think that such a rule will just keep us from the temptation to launch an engine that's usually next to such a board.)

Sounds good. I've done enough research tonight. So whenever you're ready, I'm ready to go.

All right, I've started our game, here's the link to its thread for ease of future reference. GL!

Let's return to the suggestion about conditional moves/lines:

Imho conditional lines (CLs for short) can be set up in spoilers so that they follow the same algorithm as on chess.com.

In short, because observers can see all texts of both players, they're encouraged to voluntarily do the 'arbiter' job of checking and relaying conditional moves (CMs for short) that chess.com's correspondence server would do automatically.

0. Assume that Black wants to set up a CL: 1. f3 (f4) e5 2. g4 Qh4#, meaning the following: 'if White plays 1. f3 or 1. f4, then play 1... e5 for me automatically in my absence, plus, if my first CM (1... e5) gets triggered and then White plays 2. g4 (either manually or conditionally too), then automatically play the 2... Qh4# CM for me too'. Obviously, every White's move should be followed by not more than one Black's response.

1. He writes the CL into a spoiler that is specifically marked as containing CLs and can, as usual, be read only by himself and observers but not by the opponent.

2. White eventually posts his pending move (Black might be sleeping or otherwise AFK or busy at this time).

3. Any (preferably first) observer who reads the thread after that looks up Black's preceding conditional spoiler (CS for short) and, if one of the White moves anticipated there matches White's actual move, the observer announces Black's CM. Otherwise the observer announces that the actual move doesn't match any of the CLs and it's now Black's turn.

E.g. in our case, if White has played 1. c4, no extra move is made, it's Black's turn and he must post a move himself (revisiting the thread).

If White has played 1. f4, an observer announces the CM 1... e5 is auto-played for Black, but doesn't disclose any other/further moves/lines from the CS, and it's again White's turn.

If White has written a CS for his 2nd move, the same observer should check whether it matches Black's 1st CM. If White has written a CL '1... e5 (e6) 2. g4', then g4 gets played for him automatically and then immediately 2... Qh4# is played also automatically.

If White hasn't written a CS at all or the observer finds that White didn't anticipate 1... e5, White must now make a move himself.

If he now plays 2. fxe5, an observer (possibly another) sees that White's second move predicted in the spoiler doesn't match it. Black then must make a normal second move himself.

If White plays 2. g4, an observer who looks the spoiler up finds that it matches the actual move and announces 2... Qxh4#.

Note that, even if no observer has looked the spoiler up between White's move and Black's return to the thread, Black can post the move himself regardless (I think he should be given the right not to announce whether White's move was anticipated in the CS - after all, it's observers' fault that none of them has looked up and played the move earlier if it happens to be conditional).

However, a 'semi-touch-move' rule should apply: if White makes one of the moves predicted in the CS, then Black can't make a move other than the one he specified in the spoiler, even if no observer has dug it up.

Of course Black has the right to cancel a CS and/or to post a new/edited CS at any time before White plays his move. The last posted CS for a certain move (say, move 15) prevails until White makes that move (move 15); if White's move triggers a CM, then the content of the CS is carried over to the next move (move 16) with the actual 15th White's and Black's moves deleted from the CLs (as they've already been played).

Let me give a more extended example of how a conversation may unfold.

W = White, B = Black, O1 (O2) = Observer #1 (#2)

***

B: CS


W *** gets up ***: 1. d4.
W:

W: CS

O1 *** reads both spoilers ***: 1. d4 Nf6 2. c4 e6, W is to make move #3.

B: CS

*** goes to bed ***

W: 1. d4 Nf6 2. c4 e6 3. Nc3.
W: CS

*** goes to work ***

O2 *** reads all the spoilers and applies Black's 1st spoiler and White's 2nd ***: 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Qc2, B is to make move #4.

It's a great idea, c.oon.

I prefer this format:

if 1. f3 (f4), then 1.-e5 2. g4 Qh4#

Conditional lines:
if 1. e4, then 1.-c6 2. d4 d5 3. e5 Bf5
if 1. d4, then 1.-Nf6 2. c4 e6 3. Nc3 Bb4

"If X, then Y" simplifies the reading process tremendously.

I condensed your explanation (superfluous detail is the victim).

Just make sure there's a clear format for conditional moves, and nobody thinks that a player's musings are committing them.

one time i read a story about a guy who played as black 1. b6 and then included 2. (any move) Bb7. white then played 2. Ba6 Bb7 3. Bxb7.

sounds hella complicated, in postal games you used to just write down any conditional lines so the opponent can see them.

Rei, you're a genius, I'll adopt this

Kyle, I'll avoid the confusion by putting conditional moves in a separate marked spoiler from all other musings.

Fwiw, I'm a big ethusiast of chess.com conditional moves. In fact, today, moves 2-8 of my Black game in our match vs Hajduk Split have all been played automatically as conditional because White's development vs the Leningrad Dutch is pretty predictable (I went to bed without submitting a cond. line for move 9, as I was too tired to think; I wouldn't have guessed right anyway). 7 cond. moves played out in a row are my new record

similar things work in blitz as well

A sad thing is that I did this OTB in the most important tourney of my career 13 years ago, even sadder was that the defeat was to an [average-looking at best] girl (vs 1. b4, to be precise, moreover, I had known both that it was her favourite opening and that the long diagonal had to be watched out for), and hence I ended up running 0/3 vs girls lifetime, which must have ****ed up my relationships with half the mankind I still ended up earning the class (equiv to 1700 FIDE), but had to win 3-4 games in a row at the end.