Would a 75 Move Rule be better than a 50 Move Rule?

(But if by "you" in the second case you mean me, then I would usually have to agree.)

I notice that Galen claims the 115 move position is drawn by virtue of the 50 move rule, but he doesn't give the solution. It must vary quite considerably from the one I've seen.

Re the DTZ50, I'm not sure how the inclusion or exclusion in an individual tablebase alters what I said.

You were probably looking at a DTM analysis (traditional theoretical analysis ignoring the 50 move rule). It's usually possible to get through the mate against a DTM EGTB without running into the draw (but maybe not always possible - I don't know).

Syzygy (DTZ50) is more accurate under Competition Rules, so:

If it had been Syzygy v Nalimov, Syzygy would probably have won, but not as quickly. Nalimov v Syzygy definitely draw. Nalimov v Nalimov unpredictable.

If that's not the position you had in mind (there are two ignoring reflections) then set up your position here https://syzygy-tables.info/ and click on the download icon at the bottom of the move list.

Or maybe it was another 80 moves after the pawn moves...not sure. I have read tablebase info before and it's hard to remember.

The pawn was just outside the Troitsky line, in this position, or even this one would have won:

Another thing to add is that the side with the pawn doesn't necessarily make perfect moves, especially under time pressure, so it might only take 60 moves, not 115, but still more than 50. 50 leaves little to no leeway.

Wait what? I thought this position was the longest, mate in 551 moves:

Ok, the mate transposes into a 545 move pawnless endgame form here, but what does the 1024 move position look like?

@EndgameStudier

The pawn was just outside the Troitsky line, in this position, or even this one would have won:

Or this:

1.Kb3 Ka1 2.Ne5 Kb1 3.Nf3 Kc1 4.Kc3 Kb1 5.Nf4 h3 6.Nh2 Ka1 7.Kb3 Kb1 8.Nd3 Ka1 
9.Kc2 Ka2 10.Nb2 Ka1 11.Nc4 Ka2 12.Kc3 Kb1 13.Kd2 Ka1 14.Kc1 Ka2 15.Kc2 Ka1 16.
Kb3 Kb1 17.Nd2+ Kc1 18.Kc3 Kd1 19.Nb3 Ke1 20.Kd4 Ke2 21.Ke4 Ke1 22.Ke3 Kd1 23.
Kd3 Ke1 24.Nd4 Kd1 25.Ne2 Ke1 26.Nc3 Kf2 27.Kd2 Kg2 28.Ke2 Kg3 29.Ke3 Kh4 30.
Kf4 Kh5 31.Kf5 Kh6 32.Kf6 Kh5 33.Ne4 Kh4 34.Kf5 Kh5 35.Ng3+ Kh4 36.Ngf1 Kh5 37.
Ne3 Kh6 38.Kf6 Kh7 39.Nf5 Kg8 40.Ke7 Kh7 41.Kf7 Kh8 42.Kg6 Kg8 43.Ng7 Kf8 44.
Kf6 Kg8 45.Ne6 Kh7 46.Kg5 Kg8 47.Kg6 Kh8 48.Kf7 Kh7 49.Ng4 h2 50.Nf8+ Kh8 51.
Nf6 h1Q 52.Ng6# 1-0

White actually mates in 52 from here, used Lomonosov Tablebases to evaluate.

@172, like that one cause there's TWO Mating moves at the end, rare in a 2 knight vs pawn ending!

Endgame tablebases are only up to 7 men so far, so your 545 move ending is very unlikely to be the longest. I would also have expected pawnless endings much longer than 1024 to be discovered when the 24 man EGTBs come along. 

MARattigan: That's the position of the 115 move win, and in Syzygy vs Syzygy it finishes in a draw? Now there's a surprise. (I notice that ECE deviates from this solution as early as move 12, when it goes 12.Kg4.)

Are they up to 8 yet?

Both of those moves are optimal in traditional theoretical (DTM) terms. Don't expect just a single line of play through a database. Black's next move 12...Kf5 is not optimal in DTM terms, the only good move is 12...Kd6, but in DTZ50 terms 12...Kf5 and 12...Kd6 are equally good and it happens to choose the former. That would be inaccurate, but not drawing, under Basic Rules, but is effective at least under Competition Rules. I think it's also the quickest way of reaching the draw from what Numquam told me in a different thread (at least against itself).

For best play (effective and efficient) with the 50 move rule in effect you need a DTM50 tablebase, as explained in the link I gave you earlier, but they're not generally available and I doubt if anyone has a hope in Hell of working it out for themselves.

The position is a win for White under Basic Rules but a draw under Competition Rules; a so called "cursed win" (but I think "cursed 50 move rule" would be a better epithet).

Er, not as far as I know, otherwise I wouldn't have said they're only up to 7.

As far as I am aware, the 75-move and over 75-move rules were cancelled years ago (edit: 1997). The new 75-move rule does not have the same function, since either player can claim a draw at any time from 50M upward. So it is only about both players trying for a win or the players temporarily losing track of the count. To prevent the game taking too long and disturbing tournament schedules the 75 move upper limit was introduced. It is especially useful in digital environments permitting the interface to terminate games.

@Numquam

@EndgameStudier

@BonTheCat

Out of interest I show the mate in 128 with the 50 move rule in effect.

                                                         Black to play.

                                                         Basic rules: White mates in 85

                                                         Competition rules:

                                                              PC=0,1 White mates in 108

                                                              PC=2,3 White mates in 110

                                                              PC=4,5 White mates in 128

                                                              PC>5    Draw

Here PC is the ply count for the position under the 50 move rule

Edit: Removed some crap here before someone pointed out that it was. Be aware that the Syzygy online site silently resets your PC to zero before generating a sample game.

Also the pawn doesn't have to move to break the stalemate, it just needs to sit there and get in the way.

My digital environments chop me at 50 moves, even when I'm playing myself and neither of me has claimed.