Nope, wannabe-Nussy, it sure as heck ain't.
Brewski Bob mistakenly thinks he knows English:
"Those pills used to weigh..." Although you used "did", your statement wasn't a negative:
[link|http://www.bartleby.com/64/C001/065.html|http://www.bartleby.com/64/C001/065.html]
Huh?!?
Lissen'up, numbchucks, and I'll try to explain this real slow: The verb "use" and its tenses work like any other verb when combined with "do" in its different tenses. That's actually what that overly-authoritative style guide is trying to say, but they're so bad at expressing themselves clearly that I'm afraid you may have got hold of the entirely wrong end of the stick.
We use the verb use in its past tense with an infinitive to indicate a past condition or habitual practice: We used to live in that house.
This, though, has the danger with it that since the *present* tense of that construction is used much more rarely, people may not be aware that that would mean a *present* "condition or habitual practice": "We use to go to the zoo all the time" is a perfectly correct -- but rather rare -- way of saying that we're in the habit of going to the zoo *now*.
Because the -d in used is not pronounced in these constructions, people sometimes mistakenly leave it out when writing. Thus it is incorrect to write We use to play tennis.
Well, unless you *mean* that you "use to play tennis" all the time *now*, of course. Bartleby -- whoever he or she is, or they are -- is only saying that that's wrong if you use it to indicate that you useD to play tennis *in the past*; they're warning that just because it *sounds* as if you were saying "We use to play tennis", there's nothing magic about the verb "use" (in its present tense) that makes the whole sentence past tense.
When do occurs with this form of use in negative statements and in questions,
Or, for that matter, in an ordinary positive statement. Only, circumscription(? term?) of verbs in the present tense with "do" is exceedingly rare in English (as opposed to some other languages); actually, it's only regularly used for emphasis, as far as I know: "But, Mom, I *do* eat my vegetables every day!". (But you could be a little *less* emphatic by leaving out the extra stress on the "do" [and the exclamation mark], and *just* use "do".)
It's more frequent in negative statements and questions, as well as in the past tense, but there's nothing magic about "do" (or "use", for that matter) that means that the use of the verb *alone* indicates a past tense -- it's the *tense of* this auxiliary verb that gives the tense of the whole sentence (or clause). Also, once you have an auxiliary verb to give the tense, the main verb always takes the, um, "infinitive"(?) tense; the one you use with "to", as in "to eat", "to sleep", etc... More on this below.
the situation is reversed, and use to (not used to) is correct: You did not use to play on that team. Didn\ufffdt she use to work for your company?
As per the above: "I eat", present tense; "I ate", past tense; "I do eat", present tense; "I did eat", past tense; "I did ate", no sense.
And this is the other side of the coin that the unfortunate mumble-mouths at Bartleby's are trying to warn against here: "I did used to" is just as nonsensical as "I did ate", so don't use anything but "use" with "do".
Too bad they're gibbering about "this form of use in negative statements and in questions"; it works just the same with ordinary -- or rather, not so ordinary -- positive statements. No doubt this has contributed to your confusion on this whole issue.
Heck, their explanation was so jumbled up that I wouldn't be surprised if a whole lot of people -- and unfortunately, it looks like that includes you, Bob -- come away with the impression that "We did used to [whatever]" was the *correct* construction for an ordinary non-negative non-question statement... FYI: It sure as fucking Hell isn't.
Anyway, to get back to your initial claim:
Although you used "did", your statement wasn't a negative
Compare that with your Pomposity Manual:
When do occurs with this form of use in negative statements and in questions...
and with the *whole* of my sentence, spread out over the subject line and the start of the post body as it was:
"So, how much did those pills use to weigh before their weight was 'over'?"
That, Bub, is what we call with a technical term "a question". (You can recognise them, among other signs, by the hook-shaped thingy they have in stead of a straight exclamation mark at the end.) So, my usage was correct EVEN ACCORDING TO that over-rated gobbledy-gook you dug up.
The ironic thing is that, as I've tried to explain above, that it could well have been correct EVEN IF IT HADN'T BEEN a question. And Blowhardby's doesn't actually *explicitly* say it wouldn't; it just sputters so incoherently that it *seems* as if it had.
So stop trusting that shit, Bob.
HTH!