Can I use the assumption line with my boss?

[Malaika]

My boss likes to make passive aggressive personal statements/discouraging remarks/gross overgeneralizations about me/my behavior (and other coworkers but mainly me).  For example, I had to make an appointment to have a home inspection to buy my house, which had to happen within three days.  I was able to get an appointment for two days away (got the appointment Wednesday afternoon for Friday afternoon).  I emailed boss and asked for the time off as I had worked major overtime for a special event.  As it was within the same week, it would be flex time and I wouldn't have to accrue comp time.  Her response was that I must have been planning that appointment for some time and should have planned my time better.  If I had responded with "well, that's an interesting assumption", does that become unprofessional or even insubordinate? 

Does your answer change with the knowledge that my boss will see it as insubordinate regardless?  Should I use it in that case?

Thanks!

[Dandy Andy's Daddy's Love]

The entire point of the "interesting assumption" line is to have something to say when you're so flabbergasted you can't think of anything else that is polite. I think that using the the line over email is rude, because you have plenty of time to think up an actual response, unlike in a face to face conversation. It would be much more polite and professional to respond with something like "I'm not sure I understand. I made this appointment on Wednesday. Could you clarify for me?"

[Dragons 8 Cactus]

No, I would Not use the saying. You value your job, I take it. <gentle smiles>

I would clarify that you lucked out and it worked out well for you. Coincidence.

[Malaika]

I guess I value my job.  Well, let's say I would hate to lose my job over something so dumb. 

I ended up emailing back to tell her it was a last-minute appointment I was able to take advantage of.  I've also used the "I'm not sure what you mean.  Can you give me an example?" line before in similar situations. 

Good to know my instincts are accurate.  Thanks muchly!

[pootbear]

No I'd avoid anything that sounds flippant and rely on clear, concise answers. Something along the the lines of:

"I am aware that time off request for personal appointments need to be made as far in advance as possible. In this case, the time frame for a home inspection in connection with a home purchase hinged on other factors over which I had no control.  I appreciate your consideration in granting requests for time off and would never knowingly delay a request. "

When writing to a boss, especially one who seems rather inflexible or who may be hinting that your time off requests are unreasonable or excessive, I'd suggest staying very formal, polite and saving copies in case you ever need to show them to HR or the UI office.