I stripped tons of 40 year old wallpaper in order to repaint my bedrooms only to find pesky cracks at the top of every door jam and below most windows. I was a bit unnerved by this but a contractor told me it was natural and occurs when houses settle over the years. I watched a bunch of video clips online about repairing these and many recommended widening to crack with a putty knife, filling it with caulk so it would stop the crack from happening again.
I couldn't find any caulk that said it was good to use for filling cracks in plaster, so I asked one of the people in the store who brought me to the painting isle and pointed this out. There was only one tub left, so I thought it must be good.
I put it in the crack with my spreading knife the way I would with joint compound. One thing you want to make sure of is that you do not leave a lot of this on the wall because despite the packaging saying it is easily sandable, it is NOT! Sanding this was so impossible with a block, I had to use my random orbital which still could not. Finally, I resorted to scraping the excess off with a wallpaper stripper chisel. Even then, it was not even and will show up when I paint.
Another issue is that this shrinks into the crack ... it took me 3 times applying it before the crack was filled. This stuff doesn't dry too quick ... so it basically took me 2 or 3 days PER CRACK to fill it because after you apply it once, it keeps shrinking into the crack so you have to put in multiple layers over the days. I almost wonder if this will eliminate the elastic property because each layer might have a little air in between.
Overall, I understand what this product is designed to do ... but I just don't think it is worth it based on the way it performs. Who knows ... maybe the cracks I filled with it won't expand. But I tend to doubt it. And beyond that, it looks much sloppier because it won't sand off completely than if I used something different.
The version in a caulk tube was not available at any stores near me, so I had to buy it in the tub and spread it on which probably didn't help things. I realize that I am a DIY'er and not a pro but most of the pros I spoke with about this product after applying it hadn't even heard of it before.
Cons: Difficult to Clean, shrinks after application, doesn't sand down evenly, takes a long time due to reapplications