tl;dr: Do we pick up extra equity by having a completion range on the button at short-ish (10bb effective stacks), or should we just play strictly push/fold?
I have been using Holdem Resources Calculator to review my play in hyper-turbo SNGs on ACR. Because at the level I am playing there are enough weakies who open-limp, my default game tree has the first player in having the choice of calling the big blind, min-raising to 2bb, or shoving.
I have noticed that when the action gets to be heads-up and the effective stack is fairly shallow, HRC has the player on the button completing their blind with a wide range in addition to having a jamming range. (The min-opening range tends to be so tiny as to be negligible.)
For example, for 10bb effective stack, when calling on the button is allowed, button's has a 28% completion range {66+, AJs, QTs+, Q8s, Q6o-Q2o, J8s+, J3s-J2s, J7o-J2o, T5s-T2s, T7o-T2o, 92s, 96o-94o, 86o-85o} and a jamming range of 49% (55-22, AQs+, ATs-A2s, A2o+, K2s+, K2o+ Q9s, Q7s-Q2s, Q7o+, J7s-J4s, J8o+, T6s+, T8o+, 95s+, 98o, 85s+, 87o, 75s+, 64s+, 53s+}. (Effective stack of 1000, blinds 50 and 100, ante 10.)
The calling range has all but the weakest pairs, a lot of offsuit junky hands, and a few suited hands -- some junk, better suited jacks and queens, and AJs. Thus, the completion range has strong hands to call big blind jams, and still play well if the big blind checks and the action goes to the flop.
This is in contrast to the range HRC gives when shoving and folding are the only options, of a linear 62% of hands {61.7%, 22+ K2s+, K2o+ Q2s+ Q5o+ J2s+ J8o+ T4s+ T7o+ 95s+ 97o+ 84s+ 87o 74s+ 76o 63s+ 53s+ 43s}
So which is better, having a (properly balanced) completion range heads-up on the button, so that we can play more hands in position against the big blind? Or playing strictly a push/fold game?
I know at least one pro who thinks the latter. The Twitch streamer Courtiebee plays a lot of spin-and-gos on Party; she has a button completion range as well as an open-raising range or jamming range (depending on stack depth). I once asked her in her stream chat why that was. Her glib answer was, "I get to play more hands in position."
Two points to consider:
First, that playing push/fold is easier; there is far less to memorize.
Second, HRC makes its calculations based on preflop equity only. It completely omits the value of post-flop action. For at least some of the hands in the completion range it recommends, it is not going to be easy for the button player to realize their equity.
A real exploration of this would probably call for a full solver that can handle preflop ranges, like Monker, or the bleeding-edge version of PioSolver. But can we use the recommendations of tools like HRC or ICMizer as a starting point?