Let me be clear about the stuff I posted: I'm not trying to say that this is the way that anyone should build a cross for recreational use today. For that, I think you could probably build a perfectly adequate cross out of 2" x 6" lumber without cutting any joints, just drill holes and run a couple of 3/8" carriage-head bolts through the pieces, use a washer on the threaded end and tighten a nut down good and tight, it won't move and it will feel the same as the real thing.
Agreed, something like the one pictured should be strong enough for a normal person, although it lacks atmosphere and visual appeal. We want to see something more substantial, more imposing.