Yes, obviously that's the total out of the drawer opening, not the difference. That's still quite a lot to sacrifice in smaller kitches. Still a half-inch in a 12 inch drawer is noticeable and when added up over more than one...
The tradeoff there is the depth, though. There's no free lunch... :)
I replaced a set of the old single undermount roller w/ the front side rollers w/ a centermount slide type that is also able to fit in the 3/8" bottom lip thickness as a trial here. It's pretty good excepting for the 3/4 length pullout. I'm looking at the possibility of using an overlong slide for the drawer to get extra extension but haven't gotten around to actually doing it.
I've not done a new kitchen in over 20 yr where the sizes are so huge any more--even in the old houses in Lynchburg often kitchens were very small comparatively (many of them actually had the "real" kitchen in the basement or an outbuilding for the staff rather than being in the house as a full-fledged kitchen as we know it today so they had to be scavenged room taken from other adjoining areas which generally meant they were also small. The kitchen in the old farm house here which was an add-on in the 20s to the house built in the early/mid-teens has only about six feet of _total_ counter length and that includes that 4-ft of it is around a 90 that has a lazy susan in it for storage. There si space for only three drawers along the counter top row so even a half inch is a loss.
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