Oh, that's easy - inflict harm as established. It's not that I wouldn't have made it, it's just the circumstances I'd have made it were different. Because AW1's Peripheral Battle Moves included a harm-per-tick mechanism, I was much more careful about setting up the fictional position before inflicting harm, because the harm was already built into the mechanics. Now I'm much more aggressive about doling out that harm because that mechanism no longer exists.
We actually just had a pitched battle in the most recent session of our game. Major Tom (The Show) was barred entry to a settlement because he has a contagion. As a result, he decided to whip up the other contagious folks and poor rabble into a mob, that then made an attack on the gates of the settlement. Fifi (The Gunlugger) counted among her friends in this settlement the head of the local constabulary, and she came to the settlement's aid in fighting off the rabble. I bring this up because it saw examples of two things discussed in this thread.
First, it included a harm move following a seize by force roll that resulted in the Gunlugger being trapped/panicked/KO'd - at one point the Gunlugger was atop one of the gatehouse towers firing her shotgun down at the rabble (who'd tried unsuccessfully to crash a bus through the gates), keeping them from slipping through the small gap now opened by the bus. She hit the roll, blasted a whole bunch of dudes, and scared the crap out of the rabble, but totally flubbed the harm move. In this case, I had one of the attackers atop the bus (a guy she'd just shot) grab hold of her, pulling her off the rampart with him as he fell. So yes, she stopped the rabble from slipping through, but now she was outside the walls, stuck under a dead body of her own making. The rabble turned on her immediately. This was a "trapped" result on a harm roll, but it didn't invalidate her success (at least not in the moment) because she'd kept them from slipping through.
Shortly thereafter, Ace (The Driver) let loose with the MG on his war-buggy at the rabble at the gates (not knowing that Fifi was now among them). When the result of his roll to act under fire was a partial success, I chose a "worse outcome," and immediately applied 2-harm to Fifi. So yes, he shot some of the rabble, further damaging them, but caught Fifi as well in the process. I had no problem inflicting harm on a partial success because Fifi was "in battle." I'm not sure I'd have made this particular move under AW1, especially if I was using the Peripheral Battle Moves and battle-clock.
Finally, Fifi failed another harm move after a single combat roll (because, having extricated herself from the body and having survived Ace's machinegun fire, she was trying to kill as many fuckers as she could), so I KO'd her with a brick upside the head. I had no problem doing this because there was no "success" to negate - she wasn't seizing anything and had already exchanged the harm.
There was a point right after Fifi fell where her player indicated a desire to read a sitch, and I offered that it would be totally cool for her to take some time to get her bearings, but that the rabble would be curb-stomping her while she did it. I felt that in this case the "set-up" for damage to simply be inflicted upon her had already been well established. She wisely chose action over analysis, foregoing suffering further one-sided harm.