Is very clear fold with icm, getting this shove through and winning doesn't help you @ all, the stacks become still exactly the same and Gui2x still gets to raise any 2, its much better to fold and give sb a better chance to bust.
It might be a fold, but I'm not I disagree with you saying that winning the hand doesn't help you at all. It clearly does.
Here are the four scenarios for winning if you open shove:
1. SB calls/BB folds and you win a little more than 5 BBs. Obviously, eliminating SB helps your $EV substantially in and of itself. The pot also change the stack ratios between you and chip leader from about 5 to 1, to about 3 to 1 -- not too shabby.
2. SB folds/BB calls. Your $EV will increase by virtue of your relative chip stack going from about 5 to 1 against the chip leader to about 3 to 2, a big pick up. Also, you increase your lead on the small stack from 3 to 1, to about 6 to 1.
3. SB and BB fold. You decrease the big stacks ratio from about 5 to 1 to about 4 to 1, and increase your lead over the short stack from about 3 to 1, to about 4 to 1.
4. SB and BB call. This is a homerun. You eliminate the short stack, and pull near even with the big stack.
It is an interesting point that you should shove a little tighter in that situation, but folding an ace is ridiculous. You shouldn't be playing mainly to move up one or two places. The money is in the top places. If you fold, the SB busts maybe 30% of the time. If you shove the SB busts 10-15% of the time. That difference is not as important as picking the the blinds and antes etc.
the calculation is way too complex to just eyeball. there's no substitute for running sims and crunching numbers and the math is a lot more complicated than we could get into in a thread like this.
but let's just pretend everyone was as optimistic as you are, shoving 30%ish on the button with a 12bb stack and proportionately wide from earlier positions (probably wider if there are short stacks behind since they'd be calling tighter) and they kept playing like that all the way through without any consideration of short stacks. now you're likely to coast into third within the next 5 to 10 hands. the jump from 6th to 3rd is about 1/3rd of the jump from 6th to 1st. not worth it.
alternatively if everyone else was playing as snug as nick is advocating for (shoving 12% as opposed to almost 30%), and others' calling off appropriately, then maybe you would want to blast off here with A2.
i have a hard time imagining that shoving A2 or folding A8 is optimal here. it seems like it's somewhere in between. the important thing is not to be punting with A2 when everyone else has shown the propensity to shove light, and not be folding A8 when everyone else is playing exceptionally tight.
It is an interesting point that you should shove a little tighter in that situation, but folding an ace is ridiculous. You shouldn't be playing mainly to move up one or two places. The money is in the top places. If you fold, the SB busts maybe 30% of the time. If you shove the SB busts 10-15% of the time. That difference is not as important as picking the the blinds and antes etc.
The collision chance between SB and BB is very significant so there's plenty of $EV in just folding and letting them clash. But it's also very clear that with 12bb you're supposed to have r/f and r/c range and A2o will probably make it in the r/f range. Don't feel particularly strong about either option. Open shoving is almost certainly the worst play.
Is this a spot where we can/should limp big parts of our range? I don't think A2o fits well in a limping range, my recollection of how we split limps with jams is that Axo is a clear jam if we are jamming anything...
This spot can easily be solved with modern technology.
It's close, top of folding range but a fold. A3o is the cutoff in theory, which is inarguably just a tad stronger than A2o.
Everyone is ATROCIOUS at ICM so theres something to be said about exploitatively adding in a rank and a file to your shipping range beyond Nash equilibrium and putting the ball in V's court where they will likely make a mistake. Though I feel (without any evidence whatsoever) that BB will err on the side of defending too wide which bones us.
What is impossible to justify is advocating a strategy that only VPIPs >=A8, which is unbelievably, suboptimally nitty
