Only thing i would say is...Too much pre blending and you can have problems fitting the tip...becouse you will have made the well thinner, when applying the tip the ears are not so ridged and can spread out....if that makes sense.
I NEVER pre-tailor, the tips are designed to be a certain shape and pre-tailoring (particularly thinning them down) tends to make them "splay", rather than grip the sidewalls. I prefer to use different styles ( I actually use 5 different tips).
Thats what i meant....you said it so much better...