I don't know why cuemakers say it is not cost effective. I figured out how to make full splice blanks with about $500 worth of equipment. When I get the return points dialed in like I want, I will show you.
Cue makers say it's not cost effective because it's not cost effective. With some experience of your own, you'll be saying the same. We say it's not cost effective because we have been where you are, tried what you are trying, weighed the cost against the success, and from there we drew our conclusion. Maybe we are all wrong & maybe you figured out what nobody else could. It's possible. But saying it is worth nothing if you don't have even the first blank to prove it.
I know several cue makers, including myself, who know how to make veneered full splices. But there's good reason for not doing so. What you don't know is sometimes worth more than what you do know.