Hmmm... Fascinating suggestion! In going through that thread, turns out that I asked the same question there! But then I didn't actually have the tubes. Maybe that's why I got them, for all I know, but all that is shrouded in the trainwreck that is my memory. No matter, it's nice to see that tube clippers have been tried and worked, so this is something to examine. Thanks, bluebunny.
Merlin? You out there?