Petrified of the salary cap? Heh! Hyperbole does not suit you; either than or you've been unable to understand what several of us have been saying.
I'll try again, I doubt that you'll get it, but I will try.
The salary cap is real, but only over time. You can always bust it for a year or two, but eventually, you have to pay the price. ALL teams move some money into future years via signing bonuses, all of them. The trick is not to completely avoid doing this, but to minimize it. The Saints and the Falcons? They just missed on Watson because they were already blown.
You have to stay light against the cap, so you can go all in on whatever your biggest weakness is. Our biggest weakness, by far, is at OT, so we have to be willing to take a chance there. Armstead is a guy who has missed 38 games in 9 years of being the starter (about 4 games per year), and while this isn't optimal, it is the reason he is available--considering that he is a top 5 Tackle when healthy. Also, he's 31, which unlike a WR or RB, isn't old.
In my previous post, I pointed out that we are long on YOUNG Tackles on our roster and that if Armstead misses his typical 4 games, we would have adequate resources and that the players we have should even be better for watching a consummate professional in action.
Is Armstead a risk? Absolutely, but he is the right kind of risk. You may not think so, but go back and see how many people liked my original post. We may not be right, but this is the consensus opinion.