Pier_, I do remember DR urging customers not to stretch highbeams, stating it is not needed. I don't know what other manufacturers say. I have always suspected that they tell this to customers to avoid damage to the cores, not because it's actually true. Reason being, in my nearly 40 years of playing, and in the opinion of every luthier I've ever known, and every factory authorized repair person/ builder, stretching just enough (and not too much), enormously enhances stability, and to my touch, makes strings slinkier...Now, that said, no doubt one could damage a string, and it does indeed take a sensitive touch.
But this is the dilema, eh? I'm interested to know what Thomastik tells me. Seriously, though, (IME), all strings just feel like crap and slide out of tune until they're ready for replacement if not gently but thoroughly stretched.
OH MY GOD, what kind of flame fest have I started. God knows, "40 years" of experience could be 40 years of total ignan'ce, as far as any one else is concerned. If I had a dime for every person who said moving a J pickup 3/4" of an inch didn't make a difference, or the body wood or neck has no effect on sound... maybe me, and all my mentors are wrong. It's happened before.
I ought to give it a try with my next set of TI rubber bands...damn, it
is hard not to stretch those things, like avoiding fresh baked cookies!
Not so much stretching as breaking in, or waiting some days after installing new. Did you return thse to TI as well or is this the same issue that I'm misreading?