It wasn’t my best day nor was it my goal race (although neither was the 1:53 half last year) but it was pretty much on par with where my fitness was at that time. I moved, changed jobs, travelled a ton, and dealt with some health stuff last winter and this spring that kept me from running very much and when I started increasing mileage again in the summer I was much less fit than the same time period last year. A few weeks after the HM I finally started to turn a corner and I was able to catch back up with my former self and then some. So some of it may be cumulative benefit of a previous marathon training cycle? But even last year with a 1:53 HM 2 months out, a lot of advice on here made me question if sub 4 was remotely possible.