Differences between working out 4 days a week instead of 5

I'm almost at the two year mark of working out exclusively to FB. I've always worked out 4-5 days a week, but for well over a year, I've strictly done 5 days a week, following one of the programs in my rotation (Burn, Sweat, Blend, Strong, Abs).

Lately, I've thought about decreasing down to 4 days a week, completing my programs in 5 weeks instead of 4. The reason being is my son mentions a lot how much I work out. I'm a teacher and currently work out right after work. I try to set aside one on one time with my son before working out, but then I go right into my work out, then right into cooking dinner, then bedtime routine with my son. I'm not a morning person at all, so working out before he's up really doesn't work for me (plus, I go to work early as it is). I love the stress release I get from working out after work and I have the most energy later in the day. I thought if I had another free day in the week, I could focus that day on more quality time with my son.

My only concern is the results. Can anyone give me some insight on what losing a day a week might do? I did read a post from Kelli and Daniel that they work out between 3-5 days a week. That seems a little confusing, since their programs are set up for 5 days a week plus a recovery work out. Has anyone gone down a day and still sees the same results?

Thank you!