Using the current draft:

<On November 12, 1909, both masters signed an agreement for a title match in autumn 1910, predicated on Lasker retaining his title against Carl Schlechter.>

Pro: A positive sentence is normally better than a negative.

Seeing the sentence we decided next to <Tim's>, with his comment "Who talks like that?"

Nobody talks like that, except in lecture halls or maybe in scientific journals.

It's jarring, and I think we should find a way to rearrange the information so we don't need to use "predicated on" at all.

I think <Ohio's> "contingent upon" sounds a bit better.

I don't think there should be a second comma so close together-

I think something else needs to be added.

"On November 12, 1909, both masters signed an agreement for a title match in autumn 1910, predicated on Lasker not losing his title to Carl Schlechter .<9>"

This is the first mention of the title match with Schlechter.

It comes out of the blue here.

"not losing his upcoming title match with Carl Schlechter.

"not losing his previously scheduled title match with Carl Schlechter."

"not losing his title in his upcoming match with Schlechther."

"not losing his title in the upcoming match with Schlechther."

'Provided' is pretty good, actually. A more formal version might be 'with the proviso that'...

Let's see how these work:

'On November 12, 1909, both masters signed an agreement for a title match in autumn 1910, provided that Lasker did not lose his title meanwhile to Carl Schlechter in their upcoming match.<9>'

"While Lasker had no objection in principle, he had to leave France before reaching a final decision.<6> They played a second <exhibition match>-<insert match link here>- Lasker - Janowski (1909) <7> in Paris from October to November, which saw Lasker emerge as the clear winner (+7 -1 =2).<8>"

While Lasker had no objection in principle, he had to leave France before reaching a final decision.<6> Additionally, he had accepted Carl Schlechter 's challenge in November 1908.<X> Lasker and Janowski played a second <exhibition match>-<insert match link here>- Lasker - Janowski (1909) <7> in Paris from October to November, which saw Lasker emerge as the clear winner (+7 -1 =2).<8>

Source <X> would become <7> here, so the rest of the footnotes has to be changed accordingly.

The source is <5> from Game Collection: WCC: Lasker-Schlechter 1910

This is much better! There is no speculation as to how exactly the Schlechter match may have affected Lasker's response to Janowski, but we are not withholding that relevant information either. Serious improvement. :)

I'd just suggest this fine-tuning:

I was going to apologize for forgetting about the "predicate" discussion and wasting everybody's time.

Now I see that my gaffe has provoked the Soviet into action.

<Karpova: While Lasker had no objection in principle, he had to leave France before reaching a final decision.<6> Additionally, he had accepted Carl Schlechter 's challenge in November 1908.<X> Lasker and Janowski played a second <exhibition match>-<insert match link here>- Lasker - Janowski (1909) <7> in Paris from October to November, which saw Lasker emerge as the clear winner (+7 -1 =2).<8>>>

I think that "additionally" isn't the best word choice here. Something plainer is called for.

Also, I think the times actual challenges were accepted needs to be clearly distinguished from when those accepted matches were slated to be played.

I already know when the matches were played, and I find this somewhat confusing.

The chronology has to be clear to a reader who has no idea when Lasker played any of these matches.

So something like

<Additionally, he had accepted Carl Schlechter 's challenge in November 1908 to play a championship match in 1910.>

I like "provided that" as well:

<'On November 12, 1909, both masters signed an agreement for a title match in autumn 1910, provided that Lasker did not lose his title meanwhile to Carl Schlechter in their upcoming match.<9>>

I like this a lot, except that "meanwhile" doesn't fit well here for either flow or sense. Even when it is referring to events at different times, the word "meanwhile" always refers to two events fixed synchronously in lock step, which is not the case here. What's really meant is "did not lose his title in the to Schlechter before he had a chance to play Janowski," and that's not a job that "meanwhile" can easily do. "In the mean time" is better but still not optimal.

Better would be to eliminate the need for an extra time marker here altogether.

If <Karpova> does end up choosing to go with something like this:

"On November 12, 1909, both masters signed an agreement for a title match in autumn 1910, provided that Lasker did not lose his title meanwhile to Carl Schlechter in their upcoming match."

I like 'retaining' the title too.

<On November 12, 1909, both masters signed a provisional agreement for a title match in autumn 1910. That match would take place if Lasker did not lose to Carl Schlechter in a title match scheduled to begin in January 1910.>

I like that a fair bit, but I don't like this:

<agreement <<<for>>> a title match>

What about

<Jess: So something like

<Additionally, he had accepted Carl Schlechter 's challenge in November 1908 to play a championship match in 1910.>

<He had also previously accepted Carl Schlechter's challenge in November 1908 to play a championship match in 1910>>

Sorry about that:

<In May 1909, financed by his wealthy patron Leo Nardus, Janowski played an <exhibition match>-<insert match link here>- Lasker - Janowski (1909) against Lasker in Paris, which ended drawn (+2 -2 =0). Enthusiastic about the outcome of the match, Nardus proposed a match for the world championship. While Lasker had no objection in principle, he had to leave France before reaching a final decision.<6> Additionally, he had accepted Carl Schlechter 's challenge in November 1908.<7> Lasker and Janowski played a second <exhibition match>-<insert match link here>- Lasker - Janowski (1909) <8> in Paris from October to November 1909, which saw Lasker emerge as the clear winner (+7 -1 =2).<9> On November 12, 1909 both masters signed an agreement for a title match in autumn 1910, provided that Lasker retained his title in his upcoming match against Schlechter.<10>>

As <Annie> said, it looks good.

Working just from your text there, I think you need to clarify when the <Lasker-Schlechter> match was meant to be played?

So, "Additionally, he had accepted Carl Schlechter 's challenge in November 1908 to play a match in ________."

"Additonally" isn't the best word choice- It's not a word you see often, or at all nowadays.

On December 1908, Schlechter and Lasker published the announcement for a match to be played at the end of 1909, together with conditions.

On September 1909, they published an announement that a match was planned for December 1909 or either January, February or March 1910.

So too much infor would confuse the matter - claiming that the match was to take place at the end of 1909, when it didn't? Noting that they were still negotiating, when they had published match conditions back then? These conditions weren't the final ones, but we don't now when this changed.

The best solution seems to be to change the new sentence this way:

In addition, he had accepted Carl Schlechter 's challenge in November 1908 to a title match,<7> which was finally played in early 1910.

and insert a link to the Schlechter-Lasker match at the end.

So the new paragraph would looklike this (please read before commenting):

< In addition, he had already accepted Carl Schlechter 's challenge in November 1908 to a title match,<7> >

So

i before e,
Except after c,
Or when sounded as "a,"
As in neighbour and weigh. ; P