Doing iM's of later steps while still busy with earlier PE's

Question: what are your thoughts on starting to work on the mobility exercises of later PE's, even if you have not fully mastered an earlier PE. Of course, this would be outside of the regular workout and completing the iM's of the PE I am currently working on. For example, is there any problem with start working on HBP/PE2 iM or HBP/PE3 iM while I am still in the process of mastering HBP/PE1?

I did not see that @Everett Carroll answered the question in the post immediately prior to me posting this question. I would appreciate thoughts on how to integrate it, however.

Hi Hermann,

The stretch courses are always the best place to start. If you are already working on those then you are setup for incredible improvements with your Foundation iM's.

If you can't get the stretch courses just yet, a good, general place to start could be performing one to three sets of the iM that is coming next for you. In your case, HBP/PE2>iM. After your UB workout, feel free to also add in a set of your upcoming RC>iM and sPL>iM. Follow a similar setup with Core and LB. This is just an idea and there are certainly many other ways to get in your "extra credit" mobility work. 

Thanks Everett. This helps a lot.