I'm still really new at this, too, but I had the same problem with my neck. It was a nightmare, and while working on pressure and angle did help a bit, I didn't really get comfortable shaves until I got a good soap and a good lather. That made all the difference. I certainly don't mean to impugn either your wife's soap or your lathering ability, but that's what made all the difference to me. (BTW, the soap I got was MWF and I think I might marry it, if my wife ever decides we need an "open" relationship.)
Tim- I feel your pain. I'm having the same problem. I'm hopiing a day or two of not shaving will help. Yup. Take a day off if you can and give it another shot. My skin is in much better shape today.
Merkur blades irritate the heck out of my skin. I'm currently waiting on a WCS sampler pack to arrive so I can figure out which work best for me. I've heard Irridiums are good but that they're no longer available. I'm looking forward to trying Derbys and Israeli Personnas most. DE shaving takes time and patience. I still don't always do ATG passes, and learning the proper technique and pressure takes a lot of time. Some days I get nice shaves and only have a little irritation on my neck... other days I wonder why I chose DE shaving... and then I see how much I'm not spending on cartridges
I have to agree with the verdict so far on Merkur blades. I simply can't use them! There are huge differences between different blades! You have already gotten the recommendation to get a blade sampler and I can only concur. Hope you have better luck with a gentler blade!
It's too bad that most peoples first experience with DE is the the Merkur blades that come with their new Merkur DE.