Thread by @tribunaltweets

The afternoon session continues, day four of the hearing of Harriet Haynes v the English Blackball Pool Federation (EBPF)

Previous coverage may be found on our Substack page:
tribunaltweets.substack.com/p/harriet-hayn…

J Dr A - you are still with us
DA I am
J Okay. May I start by asking c ppl you've taught. Over 1000. What sort of level? Beginners/ more advanced
DA All of the above. Ppl who have never played up to pro level players
J Pro level comparable to HH?
DA Top ppl bit higher than HH.

DA Fargo rates above 700
J Your evidence - I imagine your advice to any player would be to go for fastest break speed poss while keeping control.
DA Y. Never use more power than you can control on beak.
J That's negatively. But would advice be to use as much as poss?

DA In European when no rack, balls just sit in dents, balls break apart more predictably so you don't need to use your max power.
J Main exception is when balls have their own little dents so don't touch.
DA Or where there is something that holds balls with no gaps.

J Are these exceptional situations with no gaps.
DA Possible to be gaps even here. But most of balls will be contacting
DA Good player racking for themselves will get as many balls touching as possible. Ideally no gaps.

J You would advise not using all power can control when balls are all touching
DA Y. But in ordinary play most of balls are touching even in Blackball

J Break shot more important as ppl get better. Not identified as to what level that applies. Very early stages, played for a month, it doesn't make a lot of difference.
DA Break immaterial for lower level players.
J Your level?

DA Don't have a fargo rating but ppl say it would be 650 range. Strong amateur but not pro level
J HH rating if went into system
DA 600-650 range possibly but haven't seen enough to judge.
J Break shot becoming important at your level and below

DA I think at 500 level. My experience not data.
J How would you describe players
DA 500 range - upper intermediate to lower advanced.
J At lower ability levels, not much turns on break shots. Why
DA Cos so much happens after break. Lower abilities doesn't really matter re break

DA Break is ancient history by time frame is won.
J Incompetent player breaks, may pot ball, but can't keep going after so lose turn.
DA y. If pot a ball on break, say you make the next shot, that gives you the right to decided which set of balls

you're going to pocket and that makes big impact on game and a better chance to win game. So to retract my previous statement even lower level players have advantage on break but not as powerful as higher level players
J PF c threshold above which break doesn't help.

J Increasing risk of cue ball into pocket.
DA He's assuming balls are moving randomly and equally. His sim doesn't create realistic movement of balls. Where all balls at speed hitting cushions and each other balls are randomised and can't be more so. But in

his sim balls are moving very much. Clustered still in rack area so not moving at all. Good player controls the white on the break so cue ball parks in middle of table. Cue ball isn't moving randomly as PF suggested in his testimony. High level players don't pot white v often.

DA Also, c HH fargo rating is 629
J Summarising your answer. To an extent you accept PF conclusion but only at v high velocities, higher than his modelling.
DA And also for a rack with no gaps in it. Some balls won't move v much - 30 contact points among 15 balls.

DA PF said 100, but it's 30 contact points.
RW HH is surprised she has a fargo rating...
J that was me getting my bearings. Not going to base my decision...
DA I looked online. Possible there's another HH. But has a v low robustness so not based on much data. Perhaps

from an earlier tournament and data submitted without her knowing.
J I poss shouldn't have asked but if anyone wants to explore further they can.
J You say original PF sim defective cos of gaps between balls and you say revised sim models...

DA Sounds like PF only doing one ball and two neighbours. But might be doing one ball and anything it touches. I think in his new sim he is saying all balls touching but his physics incorporated into that simulator..

[doc] He takes into account ball and neighbours. Apex ball has two. Confident what he is doing is processing collision between first ball and two behind it. Haven't seen animations, but giving full benefit of doubt. Think he is then looking at each neighbour ball separate and

looking at separate collisions..
J Does this result in a much lower cue speed needed than you think?
DA Hard questions, you guys. His sim is resulting in balls being potted in v low speeds. His figure two on page 18He said in new sim balls were being potted at 4m/sec

- I know from experience not enough speed to pot balls consistently. Later I realised, the simulator has v great limitations re the break shot. Physics totally different re the break shot.
J You don't recognise output of sim as realistic.

DA [to doc[ That is 44 m/hr. No human can do that or ever has. And distribution of balls after break - still 8 balls in the rack area. Would never happen at speeds even far less than that. 18-20 m/hr in event I saw

yesterday balls spread completely every time. No explanation other than sim is very flawed.
J You say 9 m/hr not enough to pot balls on break. How do you know?
DA Is possible to pot a ball at that speed, but v unlikely esp if gaps in rack. His whole sim is based on stats, on av

average. No good player would ever break that slowly, not anyone above intermediate player. They would never do it on purpose.
J Thank you for your patience. Does that give rise to further qs?
RW/SC No thank you.

J Very grateful to you. As I said to your opposite partner, really helpful to engage with each other and set out positions carefully.
DA Thank you. It was a pleasure.
J Stopping till tomorrow.

J Just to make sure I've got it straight Dr A. Rule c if you've potted second ball on second go, you get to choose your target colour.
SC We can provide c that.
J Thank you. 10 am tomorrow.

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