I use sr in crumble, makes it a lot lighter. Never tried in in pastry. I cheat with pies and buy sainsburys ttde all butter puff pastry. I don't think will ever be able to make puff pastry. Shortcrust is easy, and I add a little cheese for extra flavour.
You will have to use lard as well! Trust me on this - it will work beautifully.
Dh couldn't believe how good shortcrust pastry could be until I made him a pie. He said "but it's all light and flaky and soft, I thought it was meant to be brittle and hard!" His mother's pastry in other words!