1" tubular from REI is probably around, 4,400 pounds or something like that.
I bet if you break-tested your sewing you might not be all that close to the breaking strength of the webbing, but it doesn't matter. These are just foot loops, right? They are just for convenience and nothing traumatic is going to happen if they break, right?
I sewed my footloops out of 1" FLAT webbing and they've put up with a lot of abuse.
Can we see pictures? I'll show you mine if you show me yours!
love
nick