Again, I respect Allan, his innovation, his products, etc... but I think people have a huge misunderstanding when it comes to how to deal with airframe issues, Experimental, or not.... at least in my not so humble opinion.
You can follow recommended practices, such as AC43-13-1b, or you can consult the manufacturer and follow their recommended repair or modification procedures.
AC43 makes it clear that when it comes to a spar, the only authority is the airframe manufacturer. They are a lot more lenient on ribs, web, etc...
If it was me, I would repair this per AC43-13-1b. Re-prep the parts properly elliminating the obvious burrs, stop drill the crack, and install a doubler per the thickeness called out (which for this type of repair is the same thickness as the original material). I would insure that the part is not under stress and installed properly (with a washer). I would also consult the airframe designer, Van's, to insure that my repair was "blessed". This would keep the original design intact.
After consulting a couple airframe manuals, most accept a crack that does not exceed 10% of the width of affected spar if repaired per AC43...... or per their own documented repair procedure. (they show nice drawings, mostly copied right out of AC43.....)
Some do not accept any defect in a spar period, but they are not a simple spar construction like this.
I am sorry I don't agree that "beefing up" a part is a good idea. Yes it seems obvious but you do not know if you have created a new stress point somewhere else or introduced another problem. I seriously doubt Allans product will cause any harm or introduce any stress somewhere else but that is beside the point.
People are buying the product, even after 1200 hours of operation with no apparent issue. I am fine with that, but let's make sure everyone is educated on what "normal" procedures, in my opinion, should be. It is not strapping on a fix that has not been analyzed. (If it aint broke, dont fix it.)
I do not believe any manufacturer, supporter of Doug's or not, is immune from question, especially when they agressively market on this site. Allan has been good to address the questions. I thank him for that. I also believe Allan is the type of person who can agree to disagree. I hope his loyal supporters can do the same. My flame suit is warn out, but I must say I have kind of enjoyed it!