[Jeff Chandler]

The old studs can be a tad on the hard side.

Leaving aside the easy straight line, you can drill pilot holes and use screws.

[Dawggie]

“you can drill pilot holes and use screws.”

That is the idea, but those 60 year old studs around here can be quite hard and hard to drill in a cramped area.. That is why they let you use the smaller screws.