A few years back, Christmas landed on a Monday. A parishioner said to me how nice it was that he could "kill two birds with one stone" by going to Christmas Eve Mass on Sunday and having it cover both the Sunday Mass and Christmas at the same time (in other words, only go to one Mass instead of two). I had to break the news to him (he may still be upset at me for it). You cannot "kill two birds with one stone" in Mass attendance.
Every time a holy day of obligation occurs in the week like that the Church makes it clear that you must attend one Mass for Sunday (anywhere between Saturday vigil and Sunday midnight), and another separate Mass for Christmas (between Sunday evening and Monday midnight). You cannot "double dip". This applies also to those who have a dispensation to attend Mass on a weekday instead of on Sunday in certain circumstances (which a priest can do for his own parishioners) . Those people cannot get their Sunday obligation and their holy day of obligation (e.g. All Saints) fulfilled on the same day. If a holy day of obligation lands on a weekday, you must attend that day, and another Mass for your Sunday obligation.
Sadly, the reason why we have to deal with this is because many of the faithful these days are always looking for the easiest way to fulfill their duties. Few ask how to go the extra mile (though Jesus tells us that we must!). When it comes to Mass attendance, we should never seek to do as little as possible. That is comparable to those who try to get by in life with the least amount of physical nutrition and hope it all works out in the end.
Grace is available in the Mass; every Mass. Do you want a little bit of grace or a lot? Do you want to tell the Lord on Judgment Day that you did the barest minimum of the faith? Do you really want to scrape by into Heaven? Some may, but there is no confidence in living like that. Make sure that you are not cutting any corners when it comes to being a part of the Sacrifice of the Mass. Be with Jesus.