I think the member(s) were trying to say that removing one of the shocks on each side up front is a no cost experiment to see if the poor ride is all spring, just shocks, or a combination of the two. IOW, a second shock's compression resistance could stiffen the ride some.
As far as Deaver's custom springs go, yes they will ride much better than off-the-shelf lift springs because, as quality custom springs, they will have many thin, progressively longer leaves (prolly 7-10) that achieve much of the lift from a larger spring pack which enables the arch of the main leaf, and those leaves that clamp to it, to have less arch than off-the-shelf springs. They will flex well both from the thinness of the leaves and the moderate arch of each leaf, yet they will have more load handling capacity because they have more leaves backing the main leaf. Also, the thick spring pack will fight axlewrap well. I'd guess that the only reason the factory didn't offer such superior, albeit non-lift, springs is the expense.
Off-the-shelf springs, however good, will have fewer, thicker leaves (~5-6) which means that the lift comes more from mucho spring arch with a small spring pack. More arch=worse ride and more axlewrap.
Custom springs vs. off-the-shelf springs really boils down to you get what you pay for. As far as Deaver's prices, I would definitely compare them with custom springs made by
Alcan Spring in Grand Junction, CO. I think they have better prices. Probably because they have less overhead in CO vs. Deaver in Taxifornia. National Spring, near San Diego (El Cajon?) is another custom spring maker.
As you can probably tell, I'm the board's only custom leaf spring advocate. I have custom 4" lift springs from National Spring on my FJ40 Landcruiser. Great ride and articulation. I'll never go back to off-the-shelf springs. I'd rather save my money longer in order to go custom. To each his own....