Question on Progressions

I know this question has been posted before but I couldnt find it by searching. So, I read somewhere that a GB coach mentioned that if an element is too difficult that perhaps you did not master an easier element. Is that the case? So, if I am having a hard time with an element eventhough I mastered an earlier element, should I revisit it to make the later element easier to master? Furthermore, once progressing to a harder element the earlier elements do not be to be ran through or practiced at mastery, correct?

it will depend on the nature of the progression.

the way that in a plank we are working on scapular protraction, a hollowed body, there'd be reason to believe someone wasn't so thorough on their sPL progressions if their lean doesn't really look that developed.  I wouldn't expect someone to really be strong in an L-sit if they haven't worked on HBP or sPL progressions, when we're refering to the support portion of the exercise. same goes for body levers. the abs may be strong but how does this translate to also having strong shoulders? they need to be given some time to catch up in development. try doing an L-sit with your butt well behind your elbows and then try doing it with your hip in line or infront of your elbows. totally changes the exercise!

for this same reason, we need to have a pretty well developed handstand, if we plan to master the Hollowback Press. so, some of the progressions will be a compliment, where as some progressions absolutely need to be mastered to progress other aspects of our GST.