Well, I must of course sympathise with you to some extent, but really, I must far more urgently recommend that you hesitate to rely on lexicographers for cogent definitions of technical terms. Just today I had occasion to consult the internet facility of a very major dictionary, concerning "parasitoid", a matter of which I have a modest understanding. Their definition was biologically illiterate. I agree that the OED text on "Heat", to which you refer, might read more comfortably to the layman than our flowing (or non-flowing, as you prefer) stuff that we have been talking about, but really, OED or no OED, that text cannot possibly be acceptable in our WP article if we don't want to be a laughing stock, perhaps even a reproach and a byword, among our informed readership. It just won't do. Certainly you have a point in that what we have is heavy going to the innocent and with due deference to another author who eschews "chattiness", colloquiality, and comprehensibility, I insist that we should include at least introductory material that the intelligent layman can understand, but not by presenting inaccuracies for him to understand. Accuracy before comprehension, say I, though comprehension is next to godliness at least.