Originally Posted by doke
It depends on whether or not there are antes, how many people you have to get through, and calling ranges. M is the key concept when assessing the risk/reward of profitable open shoves rather than number of big blinds. Without antes, a 10 bb shove is approximately M 7 and assuming optimal calling ranges behind at a 9 handed tables, the range you can shove profitably utg is top 8%:
88+, AQo+, ATs+, KTs+, QTs+, JTs
With antes, M typically drops to 5 making it profitable to shove more hands (top 12%):
55+, AJo+, A9s+, KQo, K9s+, QTs+,J Ts+, T9s+
Notice that A2o+ and 98o+ are both well below the bottom of this range. It's old school to think you have to shove that wide as soon as you dip below 10 bbs. That may have been ok back in the day when calling ranges were ridiculously tight, but nowadays people correctly call much wider/closer to optimally. I just shoved 10 bbs utg in a turbo on Party and the small blind called with KTs. That generally didn't happen a few years ago.
"The blinds were about to go up" is sometimes used as an excuse for -cEv shoves but that's pretty old school too. If the blinds are about to go up, you're better off waiting for them to do so before shoving marginal hands as at least then you'll win more if they do get through. As your M shrinks the number of hands you can profitably shove from any position increases, so you're more likely to get a profitable spot. With M 7, you can shove top 8% from UTG 9 handed. With M 3, that rises to 19%.
Imminent increase of blinds is only a factor when they will cause your fold equity on open shoves to disappear. For example, without antes, the BB will be priced in to call with atc if you shove 3 bbs or less, so it's worth taking a marginally unprofitable shove to avoid this.
Now we're on to a different question: which is a better hand to shove, A2o or 98o. The view that 98o plays better against calling ranges than A2o is old school (and also ignores the fact that with an ace as a blocker in our hand, we're less likely to get called than without one due to card removal).
Let's look at some of the maths:
If we think the calling range is top 10% of hands, then 98o has 30.3% equity and A2o has 34.9%
Top 20%: 98o 33.1%, A2o 41.7%
Top 40%: 98o 36%, A2o 46.7%
Atc: 98o 48.1%, A2o 54.9%
So across all calling ranges, A2o has more equity than 98o. The reason why some players seem to think otherwise is unnecessary fear of domination: yes, you're more likely to be dominated when called with A2o, but this is just a small part of the time and the rest of the time you're going to be better off with the A2o. People also tend to overstate how bad it is to be dominated. A2o v AKo is only 26%, but 98o is less than 10% better. This 10% in this specific case doesn't compensate for the times we get called by, for example, KJo (98o 36%, A2o 54.9%) or tens (98o 14.2%, A2o 28.7%).
