Former secretary of state Hillary Clinton speaks during a press conference at the United Nations in New York March 10, 2015. REUTERS/Mike Segar

Hillary Clinton said "convenience" was solely responsible  for her decision to exclusively use a private e-mail account (and server) during her years as secretary of state, an explanation unlikely to fully convince her detractors (and maybe even some Democrats) or entirely put the issue to rest in advance of her soon-to-be announced 2016 presidential bid.

"When I got to work as secretary of state, I opted for convenience to use my personal e-mail account, which was allowed by the State Department, because I thought it would be easier to carry just one device for my work and for my personal e-mails instead of two," Clinton explained.

I see three potential problems with that argument:

1. Other administration officials at the Cabinet level who served at the same time as Clinton -- Transportation Secretary Ray LaHood, for one -- had single devices with both a personal e-mail account and a work e-mail account. Did Clinton require some different setup because of security or hacking concerns? Wouldn't such protocol for having work and personal e-mails on a single device be administration-wide? If there is (and was) some gray area in terms of what Clinton could have in terms of e-mail on a single device, she may lose in the court of public opinion because virtually every person -- myself included -- has more than one e-mail account on their device. Now, not all of us are the nation's top diplomat. But, still.

2. Lots and lots of people carry two devices. So, even if Clinton couldn't have two e-mail accounts on one device, why couldn't she just carry two devices? I regularly have lunch with people in politics who put (at least) two phones on the table when we sit down. In fact, my having only one phone may be the exception rather than the rule in Washington. It's, of course, not impossible to imagine that Clinton really just didn't want to carry two devices with her at all times. But the idea of doing so is totally normal, so it seems a bit odd that for that reason alone she decided not to set up an official government e-mail address.

3. "Convenience" seems like too, well, convenient an explanation. The big sticking point -- and a topic left unaddressed by Clinton on Tuesday -- is who decided what e-mails were purely personal and which were professional and, therefore, needed to be turned over to the State Department. Clinton said she sent and received roughly 60,000 e-mails during her time as secretary of state -- half of which were strictly personal. Clinton said those e-mails were "about planning Chelsea's wedding or my mother's funeral arrangements, condolence notes to friends, as well as yoga routines, family vacations, the other things you typically find in inboxes" and that she had chosen to destroy all of them. Which means that you simply have to take Clinton's word for it that all 30,000 of those e-mails were entirely personal and not one ever had anything that might be construed as work-related in them. That's a tough leap of faith -- particularly for people who are not Democrats who believe this whole "controversy" is trumped up anyway.

Clinton and her team almost certainly knew that her press conference today -- she took eight questions, which is more than I thought she might -- would not be the last word on all of this. But, what she -- and they -- undoubtedly wanted to do is lay down a primary source document (the transcript of the presser) that she could regularly refer back to when the issue comes up again (and again). "I've addressed all of those questions and I would refer you to the transcript of my press conference," you can imagine Clinton saying umpteen times in the days and weeks to come (assuming, of course, that she is put in positions where reporters might be able to ask her questions, which seems not all that likely.)

The question that Clinton and her team can't know the answer to is whether the "convenience" argument will hold up to the scrutiny it's going to get in the next few days. If it doesn't -- and, as I suggest above, I suspect it might not -- they may well find themselves backed into another corner where she may have to try to answer the "why did you do this" question again. That's a scenario no one in Clinton's orbit -- most especially the former secretary of state herself -- relishes.

Former secretary of state Hillary Clinton told reporters at the U.N. that she chose to use a personal e-mail account because she thought it would be easier to use one device rather than two. (UN Web TV)