Deletion of Lower level design

Comment: Lower level design, because it's a neologism at best and  at worst. However, '''Keep''' High level design, since it's a valid term, widely used and easily sourced (although it's a mess right now). I don't know that it was a good idea to nominate these two in the same AFD
Stance: delete
Cited policy: Wikipedia:No original research (WP:OR)