Science Note- Shortening melts at a higher temp than butter. Thus, it holds up a little better and adds some lovely lightness to your crisp, flaky crust. You can use all butter, or any combo up to 1/2 and 1/2 butter/shorening... but I don't recommend all shortening - no flavour. But it does produce a beautiful flaky crust.
Science 2- You can put the (cold) vodka and water in a (CLEAN!) spray bottle and spritz over the dough. This works beautifully so your dough does not get over-moist. But drizzling is fine.