I found that for clear tips, if using the right brand, and if applied properly; then there is no need to blend.
There's no seam. They're clear.....
BUT I have lightly etched them.
However, when I do use tips (most rarely these days), I prefer well-less Asian tips that "blend like butter". Ultra thin, you can actually over-blend them right off the nail if you're overzealous and not paying attention.
I love that they are well-less. You put them where YOU want them. There's no trimming of the well and all that nonsense, wasting time. No pre-blending either.
And, because they are so thin, they are ultra flexible and great for clients with flat nails. They don't try to 'pop up' like some stiffer/thicker tips do.
Nailiteinc.com has them, as does Sensual world (their uk distributor).
I'm sure other places do as well.
hth's