Last ten years statistics with this rig.
27,445 fish caught including bluegill, redears, largemouth bass, smallmouth bass, walleye, striped bass hybrids, spotted bass, freshwater drum, striped bass, hybrid sunfish, white crappie, black crappie, common carp, grass carp, etc. etc. blah blah blah.
0 fish deep hooked
0 mortalities, except intended morts (dinner table).
The reason for no mortalities?
I don't use this rig on windy days.
If the wind is low or absent I can stay in constant touch with the jighead, and it's kept either moving or under tension at all times with an immediate hookset.
Hopefully you can see the barbless setup that helps facilitate removal of the hook if it's in the upper palate. This prevents tearing of that delicate tissue.
Bruce is right on with his technique of being a line watcher and staying in touch with your jig/lure/ fly - this is fundamental Fishing 101. You wont gut hook a fish this way – the exception being new “circle” hooks when you let the fish run with the bait, hooking himself.
The same technique is valid whether you are suing 4# test or 20# test line. As Bruce pointed out, it is difficult in rough and windy conditions but much easier “to stay in touch” with heavier jigs with heavier tackle.
Bruce, when you start counting fish on me you force me back to my records...
Using the exact technique you describe but with heavier tackle, excluding top waters, I have documented the following Striped Bass taken from Lake Texoma in a representative ten-year period:
6799 Striped Bass between 2 and 20+ lbs
My best year was 1038 SB
Poorest was 452 SB in a flood prone year.
I am sure I have killed my share of fish by deep gill hooks, fighting big fish to death by turning from wicked structure, and general carelessness.
I fished in all kinds of weather
Using a very conservative 3 lb/fish average – that’s a lot of stripers – do the math...
Not included are literally hundreds of LMB, SMB, SB, WB, and crappie from Lake Texoma as well as many other reservoirs in this part of the country.
All fish were caught on artificials – I don’t use live bait.
This doesn’t approach your admirable 27,445 fish but until we had our ponds, I had not fished for, nor caught a BG since I was in knee pants, with a cane pole and can of worms...
Now back to rigging 1/32 oz jigs on 4# test line...
Note: Total fish landed per boat - not individual angler.
6799 Striped Bass between 2 and 20+ lbs 
