Another surgeon-hiker, here. Predictably, Nathan and I have been reading the same journals.
For a unilateral inguinal hernia that isn't recurrent I have a hard time advising either way on open vs. laparoscopic. I really do. For bilaterals and for recurrent hernias, yes, I do laparoscopic, but for most others I still do open, for all of the reasons cited. If you are being offered laparoscopic surgery for a unilateral primary hernia then your surgeon likely only does this because so many patients show up in his office who have been googling and decided that they want the newest shiniest thing, and that's a laparoscopic repair. (This is frankly the same reason that the da Vinci robot is getting so big, despite the fact that it is really only of benefit in a few narrow applications.) You would have a hard time convincing me that recovery is quicker by any *significant* degree for laparoscopic. It's surely more expensive and takes longer. The studies that were touted as showing faster recovery times are mostly from back before managed care, when people stayed a few days in the hospital after their hernia repairs, and thus how quickly you could get them out of the hospital was a large factor in total cost of the procedure. That's why they became popular. (And even then the difference was rather small.)
With either one the activity restrictions are the same during the recovery period- about six weeks.
The modern mesh repairs are tension-free, so no one walks around in pain hunched over anymore like your grandfather did with his tissue repair Back In The Day.
And yes, your quote of 20% for chronic pain is off. (Though Nathan and I may be using more formal definitions of "chronic" than you are.) You can find a study to support any position you care to, but a decent quote would be that about 10% have some sort of subacute pain, meaning lasting longer than a month but shorter than a year. A lot of these can be treated with neurectomy. The numbers who have pain lasting longer than a year and need serious management for it is in the low single digits, which yes sounds low unless you're the guy getting surgery.
That said, I would agree that the risk of specifically nerve entrapment as a cause of pain is less in laparoscopic repair. Well, unless your surgeon has a senior monent and puts a tack in the Triangle Of Pain. (Seriously- there is an anatomical landmark called the Triangle Of Pain.)
Which laparoscopic repair is your surgeon doing, TEP or TAPP?
Tom- You're right that you'd be hard pressed to find someone who did nothing but laparoscopic hernia repairs for a living. However there are specialists in laparoscopic surgery, aka minimally-invasive surgery, and there are well established fellowships for it. They might well do that many laparoscopic hernias repairs, but on the other hand it seems to me that some of them consider "routine" stuff like gallbladders and hernias to be somehow beneath them. They want the adrenalectomies, splenectomies, and other prestigious stuff.
There are also a few who specialize in hernia repairs, e.g. the Shouldice Clinic, though not necessarily just the laparoscopic ones. For instance, my example the Shouldice Clinic still does open tissue repairs! (Go figure, the repair is named the Shouldice repair.)