But, you do know that when the player gets injured, the team has a guy ready to step in? It's a depth .. chart.. And that's the time (not now, then) that they then go out to find the guy to become next in line at the requisite spot on the depth chart.
If we followed your logic, we'd need 20-25 extra players now, ready for 'when a Saint gets injured' at any position. Don't work, nice try though.
Also, I never mentioned signing starters in response to the "injured LB is inevitable" posts, so you may have been a bit confused on that one