I'll set up the scenario.
I write a blog post about particulars of the query process. You're reading and reach a particular faux pas and scream "Noooooo!" at the screen like a bad horror movie. Because you queried me two weeks ago. And committed the faux pas. You rush to your email, dig up our email thread, or start a new one with the subject "correction to query submitted Month/Day", and hurriedly (but not so hurriedly you don't forget to be diplomatic or check for grammar and spelling errors) write me a note apologizing for not knowing I prefer my queries a certain way and to please overlook the error or accept the new query. I see the email in my inbox, smile to myself, give you an e-cookie (warm, gooey, chocolate chippy, zero calories--it's an e-cookie, go with it), think "oh, you adorable dear," and delete it (not your query, I'll still answer that, non-biasedly). [query no-nos can be found in my January Query posts such as this one on What Not to Include]
This entire process is unnecessary. And you're cluttering my inbox. And wasting your own precious time.
Most things that you're wanting to correct are tiny things, things that will not sway my vote from yes to no. The exception may be if you realize you get my name wrong and catch it just after sending the email. Go to that email thread, send me another with a quick apology. I completely understand that mistakes are made. And it is nice to know you were actually (mostly) paying attention.
When you send a query... hands off! No resubmitting, no do-overs, no minor or major corrections, no additions to your bio.
Move on to a new project. Do not rework your query or ms (unless you're submitting to new agents or contests) until you've received all the feedback from your first/second/third round of querying. And since you've been concentrating on something else, you can go back to it with fresh eyes and incorporate the changes.
The only reasons you should be bugging an agent after submitting a query are 1) following up after the agent's preferred time frame to be sure they've received the query; 2) following up after the agent has had your ms for a preferred time frame; 3) to inform an agent of another offer of representation; 4) to withdraw the query/ms from consideration for a myriad of reasons including shelving the project (not suggested--get as much feedback as you can--it'll help you, if not for this project, then for the next) or accepting another offer.
And now that I've gotten half of you fretting over the tiny imperfections of your query, and the other half fretting that I hate you because you did this, I'll leave you with a reminder--
I'm not trying to call anyone out with this post. And if you find you've done the no-nos in this post, no need to follow up with another email or comment of apology. Your intentions were good, and I do appreciate it. This is more of a "keep in mind for the future" sort of post;