You definitely do NOT need 4-5 20+ milers to break 4 - so many people have done it never running more than an 18 mile long run, so get that 20-miler myth out of your head.She is not doing the long runs required, simple as that, you need four or five 20 milers in a typical marathon block to break 4 hours, all those tit miles and double days achieve nothing, their training drives me crazy
Fact: you also do not need to run 50+ miles/week to break 4 either.