[dgfitz]

I would personally not want to explain the gap in employment.

"Why did you not work for a year?"

Either you lie (I took a personal leave of absence) or tell the truth (the company was a shitshow and I didnt stay long).

I'm not big on lying, and if I tell the truth I'd expect to get "Well why did you leave it off the resume?" And from there I expect the conversation to go poorly.

[jon-wood]

It coming up at all is going to vary wildly between interviews. From my perspective your CV is what gets you into the interview process, and will come up in an initial screening call where I have a conversation with you about the last few years of work you've done. Unless you explicitly bring it up, or the work seems massively relevant to what we're doing, I'm unlikely to touch on anything more than a year or two into the past.

Once you're through that initial screening call the only influence your CV is going to have is if our interview process covers particular things you've mentioned knowing about in your CV and then you can't answer questions on them when they come up. Not knowing a thing I'm generally fine with, claiming to know it but not being able to answer simple questions on it is going to get you screened out very quickly.