t.brandt, post #7: I disagree with the framing of Air bubbles above, and I think it is a substantive disagreement rather than a terminological one. Setting out why, so it can be checked. The reasoning depends on an assumption that is doing a lot of work and is never stated. If the assumption holds, the conclusion follows. I do not think it holds generally. Go to post
Drawing up with one needle and injecting with another: a reasonable practice if you have extra needles. Fresh needle for injection reduces tissue drag and can decrease discomfort. Not necessary, but not harmful either.
Worth reading the earlier posts in this thread before acting on mine.