I agree.  think this is one of those things that sound good on paper, but extremely difficult to execute, even tho. I agree with most of the points on some level.  IF you have a supportive husband (and in this case, I do mean husband and not BF, because there is a difference between being a not so invested GF vs. a lifetime invested wife, esp. when it comes to managing someone else's children), then this becomes much easier.  Most of the SMs here, do not have the most supportive husband.

Otherwise, as a wife, you have a clearly joint household that you have to run.  There is yours and mine, but there is mostly ours in running a household, even when it comes to various SKs.  It is very difficult to ignore a SD, for instance, who leaves her crap in the bathroom and won't clean up her bedroom, and just let her pops deal with it.  What if pops also has no problem leaving his crap around?  Also, it is critical for SKs to see their dad and his wife as a husband and wife and not as dad and his side-thang.  If a SM acts like she is just there to defer to pops every time, then it will look like SM is simply dad's side-thang.  Further, what happens at family events?  Does SM just not go, because after all, these children are not hers?  Or, does she go to be by her husband's side because she is her husband's wife?  

So, to me it is not even necessarily being that invested in your step-child's outcome.  It is just the reality and the execution of all of it.  And, you have to look long term.  Sure, as a shorter-term GF, these rules might sound ideal.  But, as a full-term wife, it almost comes across as being condescending to the kids and letting them and their dad (and BM) run what is supposed to be a household that you and your husband are jointly running.  However, again, I get, "Not my monkey, not my zoo," and I get staying out of what is really another family's post-divorce issues, and I get learning to say NO, and meaning NO.