Same workout every day?

Hi everyone!

I just started 30 day shred, and like most of you who have tried it, I am extremely sore on day 3! The workout is great, and I welcome the pain as I know it is a sign of a good workout. I am happy to push through it every day and continue with her program of Level 1 for 10 days, Level 2 for 10 days, and Level 3 for 10 days. I am hoping for the same amazing results I have seen from many of you dedicated shredders on here!

My question is more out of curiousity (and somewhat out of concern). Through research and general discussions with people over the years, I have always heard how important rest days are, and that you should be alternating what areas of your body you are working out (Legs one day, arms the next, or strength training one day, cardio the next, etc.), so as not to over-stress or damage your muscles by not letting them fully recover. With Jillian's program, you are following the exact same routine with the exact same exercies for 10 days straight. Is this going to be a) not as effective because I am not letting my muscles recover, and b) potentially damaging to my muscles at all? The progress pictures on here speak for themselves, so obviously the program works, but I'm just curious as to why the lack of rest days/alternating exercies is not an issue? Would it be more beneficial to rotate through the three levels every three days rather than doing the EXACT same moves every day? Or even to do one of her other DVDs every other day?

Any responses are greatly appreciated :)

Thanks!