As this has been a good 'sharing' thread:
I was playing BF around 2002 (wow how long ago that seems, but like yesterday), in those days often just backing selections mostly.
My bank was doing fairly well - markets were a lot softer for straight punters back then too. I was cruising through a fairly usual afternoon a few hundred up on the day. Got to a large field sprint, and I noticed a selection I had fancied trading around 12.0 - there was a big gap in the other side so I thought I'd throw in a cheeky request for a lumpy stake at 25.0. But, I accidentally pressed the 'lay' at 25.0 instead for the same stake. Of course it got snatched immediately - and it was only about 10 seconds to the off. I sat there frozen, did absolutely nothing, and thought - oh well it's a massive field and it was 12's anyway, what chance.. there was only audio commentary those days, and no inplay trading....it won by 3 lengths. Can still remember listening to my funds draining away!
Destroyed me for about 9 months must admit. But it's great to look back on at times these days as a reminder.
Huge over-staking foolishness
not quite the same thing, but a similar tale of caution. back in 2015 I had been doing pretty well on matched betting. being a developer, i'd managed to find a few loopholes that allowed me to exploit more offers than I was reasonably entitled to!! (enough said already on that) 
however, I knew that things wouldn't last forever, so I deceided to take a look at BA around about that time and having a fairly nice bank to start with, set about exploring the tools that BA offered. the dutching tool looked great and i decided (on day 1) to have a pop at that. to my amazement, i somehow (luck, ignorance and bravado) managed to secure a profit of about £500 on that 1st day. I was laughing at how *easy* this malarky was and having explored automation for at least 2 hours that evening, thought that i'd setup a rule to take away *all the hard work* that i'd had to undergo earlier to make my tidy profit.
*** SPOILER ALERT *** - IT DIDN'T END WELL.
On setting up my rule, i had of course not taken into account MANY things (the main one beng that I was clueless and had had a very, very lucky 1st day). Roll on day 2 and i popped the rule on and ordered the yacht. The 1st couple of races did quite well and i therefore fancied that i could leave that running and get on with other things. It therefore came as a bit of a shock when i returned at 18:00 to find that my bank was down by over £1k.
What i'd underestimated was the fact that you couldn't just dutch every race and that you couldn't leave automation (that was literally untested) running on what amounted to full *production grade* stakes. This was as much a lesson in humility as it was one of enlightenment. I realised then that there was much more to all of this than just picking the top 3-4 runners and spreading the stake across them. Roll fwd 3 years and although dutching is still very much in the toolkit, the approach is way more rigourous and the selection criteria and filters probably end up removing 80% of all races. Also, that lesson taught me to focus on bank management/protection as that arrogant 2nd day could have wiped me out at any other time.
In short, 3 years has been an education and one that continues right to this day.
however, I knew that things wouldn't last forever, so I deceided to take a look at BA around about that time and having a fairly nice bank to start with, set about exploring the tools that BA offered. the dutching tool looked great and i decided (on day 1) to have a pop at that. to my amazement, i somehow (luck, ignorance and bravado) managed to secure a profit of about £500 on that 1st day. I was laughing at how *easy* this malarky was and having explored automation for at least 2 hours that evening, thought that i'd setup a rule to take away *all the hard work* that i'd had to undergo earlier to make my tidy profit.
*** SPOILER ALERT *** - IT DIDN'T END WELL.
On setting up my rule, i had of course not taken into account MANY things (the main one beng that I was clueless and had had a very, very lucky 1st day). Roll on day 2 and i popped the rule on and ordered the yacht. The 1st couple of races did quite well and i therefore fancied that i could leave that running and get on with other things. It therefore came as a bit of a shock when i returned at 18:00 to find that my bank was down by over £1k.
What i'd underestimated was the fact that you couldn't just dutch every race and that you couldn't leave automation (that was literally untested) running on what amounted to full *production grade* stakes. This was as much a lesson in humility as it was one of enlightenment. I realised then that there was much more to all of this than just picking the top 3-4 runners and spreading the stake across them. Roll fwd 3 years and although dutching is still very much in the toolkit, the approach is way more rigourous and the selection criteria and filters probably end up removing 80% of all races. Also, that lesson taught me to focus on bank management/protection as that arrogant 2nd day could have wiped me out at any other time.
In short, 3 years has been an education and one that continues right to this day.
