My money is also on the fake supply tactics, it's easy to make your move while two other forces are at their throats. And it would explain why they won so fast. But I also like the thought of greenhand with the God's Wood after this hints to these "CotF tunnels". Although it would be surprising that no one would have figured this out before (+ if Connington knows why hadn't he told Mace back then during Robert's Rebellion? Or did he already lost his battle by then?). Anyway I didn't knew the Sandsnakes got 300 Dornish soldiers with them. I thought it would be just them with some guards. I was wondering anyway what would happen with them if Doran declares for Aegon while they are in King's Landing. Can become interesting when Mace and his host leave King's Landing. I mean, then there should only the Goldcloaks are left, how many of them were there left by the time of AFFC/ADWD? If Tyene can influence the Faith's troops for their favour + the 300 spears they can unleash a big shitstorm in King's Landing/Red Keep with a good planned night operation. Actually I think when this other Tyrell army, which is marching for Storm's End is defeated Mace will make a move.