Sour cream sandwich bread

I made Dan Lepard's Sour cream sandwich bread and it rose nicely with some oven spring although still not a huge amount. Even though the recipe uses 550g flour compared to my normal 700g it ended up taller than my loaf recipe although using 100% white flour must help. The sour cream may be the secret ingredient though and I will have to try adding it to my bread to see if it helps.