90% correct speculation seems a bit hard to achieve, but I believe there are some people capable of doing it, if you want to become good in trading then you need to learn by yourself not by following some signal, but if you want to try to see the accuracy of the signal then go ahead, maybe you can learn something from the signal
This. I could be right 99% of the time but I'd barely make a cent, whereas alternatively people can be right 50% of the time or even less and make a very handsome profit. I would say to always stand on the side of caution and remember that if something seems too good to be true, then it probably is.