I am working back from a lengthy flying hiatus and one thing that I'm doing is looking at random approach plates and mentally flying them. I came across the VOR/DME Rwy 23 approach for KDYL and I have a question about approaches that contains an IAF other than the NAVAID used for the approach. In this case, GROOM is an IAF but how does one legally get to GROOM since it's not part of any en route structure (I checked the en route chart for that area)? I'm sorry to be so simple minded but I just want to make sure I'm interpreting this correctly. Thanks in advance.