Henry, we were discussing and cussing the pros and cons of using Sanding Sealer in lieu of Wood Conditioner and if there is actually a difference.
I have always used Sanding Sealer as my prep for all wood when about to stain. I have always been told that sealer will reduce the variable in staining penetration and stain colors. I have always had very good luck with it.
Then Bruce informed me that I would get better results with conditioner than sealer. I tried the conditioner on oak and got such a barrier that I could NOT wipe on more stain to achieve a darker stain. The conditioner made a barrier.
Now, I am told that oak does not need conditioner mainly because of its density.
My home centers do still sell conditioner and sealer side by side.
jb also had some very good info and advice and a site that I will research.