I would be very inclined to go over the cracks with Easysand, then prime and paint.
If the cracks are stable they wil not be back. If they are not stable they will re-appear and then you can decide how to proceed.
If they are from a foundation repair they should be pretty stable.

Hi,
I have had some luck painting spiderweb cracks in my plaster with Link or Plasterweld bonding agent. It's sort of like elmer's glue. It is worked into the cracks and really holds the adjacent "tectonic plates" together. This is just one of the great uses of bonding agent for old plaster.
I feel that caulk is the wrong material in this place. The cracking was the result of a one-time event, not (we hope) from repeated circumstances. Caulks have their greatest usefulness bridging joints between dissimilar materials- wood/metal, wood/masonry, metal/masonry, etc. Where the materials have ongoing movement issues due to varying rates of expansion/contraction. That's not what's happening in the scenario you have described.
Casey

Thank you for your responses. The cracks are fine lines and the plaster is snug against the lath. I will incorporate your suggestions in formulating a solution!

I have used that process on drywall problems and plaster over block with success. I have not seen the cracks reappear, but depending on temp changes you can slightly see where they were. Over all I found it a good solution.

Paul

I also heard about elastomeric paint for repairing and protecting hairline cracks in preparation to paint my interior walls. I've been to both Home Depot and Lowes and they look at me like I'm crazy when I ask for this type of paint. What brand did you use and where did you buy it?

I'm a professional residential and commercial painting business owner. Benjamin Moore and Sherwin Williams both carry it as does home depot and lowes. The employees at either box stores have no idea its on the self. If you you look where the exterior paint is - the can says Elastomeric Masonry, Stucco and Brick Exterior Paint.

I've used products from all three (Benjamin Moore, Sherwin Williams and Behr), take it from a professional and do yourself a favor - buy Benjamin Moore or Sherwin Williams. Remember there's a reason why these two companies' products cost more than Behr paint. You get what you pay for in quality, performance, coverage, and you have two major paint and coatings companies that specialize in only paints and coatings with great quality control. BTW they do not sell screwdrivers, wrenches, dishwashers, carpeting, tiles, plumbing, and so on. Point made.

"BTW they do not sell screwdrivers, wrenches, dishwashers, carpeting, tiles, plumbing, and so on. Point made."

On a 13 year old thread you felt the need for that?