Dr Slicer's Holy Grail riddle

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Jojo Apollo
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Dr Slicer's Holy Grail riddle

Post by Jojo Apollo »

An interesting read of a football betting strategy that supposedly guaranteed a profit:

https://exploitativebetting.co.uk/dr-sl ... -debunked/
Dr Slicer’s Holy Grail Betfair Strategy – Debunked?

A couple of years back, I came across an article about a riddle called “the Holy Grail” that someone called Dr Slicer apparently placed on the Betfair forums. Basically, a guy called “Dr Slicer” said he could do a trade on football and guarantee a profit.

This was before my time. Therefore, I have just got the criteria from other websites that describe Dr Slicer’s criteria.

I haven’t solved this riddle. However, I believe that I can debunk this riddle.



Dr Slicer’s Criteria

The criteria for this method include
1.Placing 2 bets before kick off:
a. The First bet is Laying 0-0 correct score at half time
b. The Second bet is guaranteed to lose should the first bet win

If the first bet loses, the score will be 0-0 at half-time.

2.A third bet is placed at half time and an adjustment of the second bet may be needed.

Dr Slicer didn’t say what bets 2 and 3 were. Apparently, he claimed that using a staking strategy, he was guaranteed a profit between 9 and 12% per match.

There was a 3rd criterion and, as I will explain later, this criterion tells me that something is amiss.

3.The home team has to have a clear advantage.



What is the Second Bet?

Most people believe that the second bet is to back 0-0 at full time. There aren’t that many bets that lose when the score is not 0-0 at half-time. There is 0-0 at half-time of course. However, it’s kind of pointless betting 0-0 at half-time and laying 0-0 at half-time.

So, what other bets are there? There is under 0.5 goals but that is the same as backing 0-0.

In criterion #2, Dr Slicer talks about an adjustment of the second bet if the first bet loses. This implies that the second bet is still live at half-time. I can’t think of any bet that loses if a goal is scored and is still live at half-time when the score is still 0-0 other than 0-0 at full-time.

I have to admit that I spent hours trying to work this out and gave up.

Then, I came back to it months later and gave it another try.

This time, I noticed something that didn’t add up. I will explain why I think doesn’t make sense. I might be wrong. If anyone has information that debunks my conclusion, they are welcome to comment. If I am wrong, I will admit I am wrong. I don’t have a problem with that.



The Contradiction: The Requirement of a Home Side Advantage for Guaranteed Profit

What didn’t make sense was the phrase “guaranteed profit” together with the requirement that the home side needs a clear advantage.

When Dr Slicer says that the home team must have a clear advantage, he has diverged from just using odds and probabilities.

If you were basing a system solely on numbers, it wouldn’t make a difference whether the home side or the away side is a clear favourite.

If Dr Slicer says that the home side (as opposed to the away side) needs a clear advantage, he is implying that his system needs a goal to be scored. People, who lay the draw, often have a preference for the home side being the favourite.

I have found that the main problem with Dr Slicer’s method is that, the liability on the first bet is too big for any second half strategy to recover in full. This liability is especially large when the home side has a clear advantage.

For the third bet, the first thought that springs to mind is to lay the draw with the 0-0 full-time bet covering the 0-0 result. However, you will have lost too much money from the first bet (laying 0-0 at half-time) for lay the draw to make a profit. You will make more money back when the favourite scores but it probably won’t be enough to break even. If the non-favourite scores first, you don’t have a chance of winning your money back (unless the non-favourite scores the first goal very near the end of the match).

In any case, lay the draw wouldn’t fit the criteria because there is no fourth bet, which you would need to cash-out after a goal has been scored.



The Home Side Advantage: Is this a Fallacy?

The lay the draw gurus believe that, a favourite home side will always be trying to win. They are unlikely to settle for a draw. Home sides tend to want their 3 points badly.

By contrast, an away side may settle for a draw even if they are favourite.

That is their logic. My logic is, isn’t home side advantage versus away side advantage factored into the odds?

Say, you have 2 matches.

The first match has half-time odds of:

0-0 Correct Score: 4.0

Team A (Home): 1.43

Draw: 5.0

Team B (Away): 8.2



The second match has odds of

0-0 Correct Score: 4.0

Team B (Home): 8.2

Draw: 5.0

Team C (Away): 1.43



So, Team B features in both matches. In the first match, Team B is the away side and in the second match Team B is the home side.

So, my question is, are the 4.0 odds for 0-0 in the first match different from the 4.0 odds in the second match? Of course, they aren’t. Is Team A’s strength over Team B the same as Team C’s strength against Team B?

What I’m getting at, is let’s say you moved both matches to a neutral ground at half-time. Now, Team A’s odds would lengthen because they don’t have a home advantage and Team C’s odds would shorten because Team B doesn’t have a home advantage. Therefore, if you don’t take the home and away factor into consideration, Team C is likely to be a stronger than Team A.

So, the home and away advantage are factored into the odds. It might make intuitive sense that home sides are more likely to be motivated to score. However, in trading, intuition is dangerous, especially when you are choosing intuition over the numbers. Your intuition may be wrong. By contrast, the numbers are less likely to lie.



Conclusion

The criterion that the home side must have a clear advantage, suggests that part of Dr Slicer’s system is dependent on chance. Therefore, I can’t see how there is guaranteed profit.

You also have to remember that, if any side has a clear advantage, the pre-match odds on 0-0 at half-time are going to be quite long. This means that your liability on laying 0-0 at half-time will be large.

I’ve messed around with the numbers. If the match gets to 0-0 at half-time and you lose your bet against 0-0 at half-time, I don’t think that there is a way to win this money back and make a guaranteed 9-12% profit.
Gavin Chipper
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Re: Dr Slicer's Holy Grail riddle

Post by Gavin Chipper »

I was hoping for a bit more when I read that. It's basically:

1. Guy reckons he has a foolproof betting strategy but I don't know what it is.

2. I don't think he has.
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