From; Roulette, dealer signature myth or not.
This is one of posts from closed forum, with some editing I will try to explain how well prediction based on dealer’s signature can be.

Red line at bottom of the picture represents remaining time until ball hits rotor.
Coloured triangle with blue green and yellow areas represents quality of wheel that we may play. With better quality wheel with of coloured area will reduce and we will have better accuracy.
First vertical red/black bar 1 located at 6 sec to the end, has 4 numbers in blue area which means that ball with same speed will 50% of time start failing within 4 numbers of accuracy.
20 of time it may be 7 numbers,
20 of time it may be 10 numbers
And 10 % it may be anything.
Simple meaning of this is that from 100 spins where the ball is 100% same 50% will hit at same spot within 4 numbers of tolerances, but remaining will be around or even completely out of order. Reasons for that are deformations on the wheel, slight tilt, the ball is never 100% rounded dints on the ball or ball track etc.
If we look bar 2, at 10 seconds to the end we can see that errors do increase. For example 50% of hits will be within 8 numbers. This is only simple representation; of course that increasing does not have to be linear with time but definitely is proportional.
Once when we get prediction there is no way that we can predict how ball will be affected by all deformations on the way to the end of spin and it is regardless what was the ACC at that moment.
It’s same as shooting arrow all the time with same force, on rainy and windy day.
Even the arrow starts with same force and same angle, first drop of rain effects it. Based on how firs rain drop effects it, next drop may have completely different effect. On top of that slight changes in wind, different at any single point of arrow traveling time would affect final result even more…
It will result that some arrows will finish 100 meters from us + or - 5 meters, but some +or -10 or even more. However if we observe same arrows with same speed where the target is only 50m distanced, differences in between final results will be smaller.
Looking above picture try to imagine how much error will increase with 15 sec. to the end. That would be one of shorter spins for dealers signature play. So even if dealer spins the ball exactly same every time we would not have much chance. On top of that consider back spinning of ball at first few revolutions which again is not constant. Finally consider change in rotor speed. If rotor changes from 3 sec per revolution to 2.8s it is not significant change for naked eye but it makes 1 number per second difference therefore result after 15 sec will be 15 numbers different. I think that this explains why even if dealer spins the ball every time 100% with same speed we cannot expect that ball will end up at same place.
If we play tilted wheel that may help but that is only helping in previous example if dealer spins the ball with force to make 15 or 15.5 revolutions. On tilted wheel result will not be 0.5 rotations different but it will be close to same or it will shift by how much the wheel changes until ball makes extra ball rotation.
It is because tilted will makes various ball speeds to fail at same point. Sounds good but there is additional problem, the ball that pass dominant diamond even if it has similar speed may continue for additional full rotation and in most cases end up on opposite side. So it does not help much. On tilted wheel because of all described problems that ball may face on the way to final destination even if dealer spins it 100% same, some balls will make 15 rotations some 14 some 16. On top of that do not forget that we still did not add ball bouncing which buy itself in most cases is 50% random.
Let’s say that someone is using an electronics timer to help him to define when the ball is at particular speed range. If he does it about 6 rotations to the end he still is facing problems as described with picture above.
Putting that aside let’s consider wheel as perfection and look players chances to gain an advantage.
On tilted wheel to find only right ball revolution may not be good enough and way to detect ball speed within particular time definitely will not find it every time.
Even if player finds it within his range, who says that all ball speeds will hit dominant diamond, for that chance is probably again 50 %.
On top of that, ball speeds that will hit dominant diamond will not travel with same speed, so let’s say if there are 6 revolutions to the end, time for that 6 revolutions will change and of course rotor will not make same distance in traveling.
It produces error of about 10-12 numbers. (on very slow wheel it may be less and part of that will be compensated buy scatter)
So player who is trying to do it first has chance of 50 to get right revolution, if he does not he is about half wheel wrong. It would be ok if that is half wheel but he has 10-12 numbers shifting on each half. Then again within time window that he defined for targeting particular ball revolution not all ball speeds will hit same diamond. Add slight error if wheel changes speed, add randomness of ball bouncing and he really does not have much chance to have advantage. In some occasions it may be but it is very minimal. His chance may increase with very slow rotor, very strong tilt and of course if he starts making accurate adjustments for change of rotor speed. Skilled visual player gets only 10-20 advantage.
Knowing all this if we go back to 15 sec at start of spin if we consider that dealer will never spin with 100% same strength, if rotor is never 100% same, if ball while spinning can be differently effected, if ball bouncing is partly random, if even defining close ball speed at only 6 revolutions to the end, hardly can produce any advantage, we definitely can say that dealer signature will not work on today’s casino wheels.
Some people in casino trying to play it even ignoring that few spins with ball lending same distance from starting number were actually when ball was spinning in different direction.
I place my early bets mostly based on theory of dealer’s signature. Sometimes it can be very profitable, but it is only trend. In most cases I see that ball and wheel are going with different speed and I still get same result. It is luck. Trend comes and goes, we never know when it will come or when it will go, and therefore we really cannot take advantage of it.