Actually, in real world, would not pull anything super heavy with loader anyway, that's what the drawbar is for, but
we all do things with loaders we shouldn't...
That's the answer to your question, Drew. You never know what might come up, and you never know what the next owner of that tractor might do, either.
I'd be very surprised if you could even get one square inch of bond with one of those hooks, let alone three. If you're using one of the 60XX or 70XX electrodes, you're getting 60,000 or 70,000 pounds of ultimate tensile strength, the force needed to break the weld. Yield strength is typically somewhere down around 36,000 to 40,000 psi, seven or eight times the strength of the glue you referenced. Even if your welds are full of holes, they'll still be much, much stronger.
BTW, if you're leaving your coated electrodes laying around in the barn, they've probably absorbed water and that's where the porosity is coming from. Try drying them in your oven for a few hours at 300F before you weld next time. And keep the barn door closed so the wind doesn't blow the shield away.
And both the Miller and Lincoln web sites have sections to help you determine the proper electrode and machine settings. Makes a world of difference!