To the authors of spam bots, or to the people paid pennies to submit spam comments – don’t you think it would be worth your while to check after submitting the spam (say after 5 days), to see if it was actually posted. If it wasn’t you can assume that it was successfully blocked, and can stop trying to submit to the same site again.
If it was posted, you can assume it wasn’t blocked and resources you save from trying to post to sites which don’t publish your posts can be re-directed at the sites which do.
Clearly this is more efficient at your end, saves you money and time, and reduces green house gasses across the planet. We can presume that sites accepting your spam either want it or deserve it, and hence are acceptable targets.
None of the spam (several thousand, a tiny amount I should think compared to real blogs) you ever try and post here makes it through and yet the same sources try and try and try again – give it up guys – it’s not working for you.