I think a lot of this depends on how you define "actual engineering". EDOs can and will do plenty of program management, systems engineering, and industrial process management. Will an EDO sit and play with AUTOCAD? No, that's not his job. But being an EDO does require a strong technical background. There's more to EDO then your what your ship maintenance rep does.
If I recall, the EDO community also used to send guys to MIT for advanced degrees. That's a far better education than a year of operators training.
I define 'actual engineering' as in sitting down and desiging something, ie 'using CAD' as you state. There are R&D spots open for EDOs but if someone is joining the Navy as an EDO and expects to be designing, for example, the next DDG as a LTJG, he's going to be in for a rude awakening. As with any community, there are more options down-range but I don't necessarily think it's sound to make career decisions based on what you could do if you commit to the Navy for a long time. Something to keep in mind, yes, but the closest alligator is the JO experience and that's all that someone who 'just wants to repay the 4 years he promised' is going to get. For an EDO, my understanding is that entails the following:
-Get warfare pin
-Go to NPS or MIT (this would apparently be a 3rd master's for OP)
-SY or SPAWAR assignment to do EDO quals, vast majority of assignments are SY.
I'm sorry if that was way off or 'bullshit.'
As for my comment about the training pipeline, you need a technical degree to qualify for the advanced coursework the EDO pipeline will put you through. My comment about the line nuke training program is they will take someone who majored in basketweaving and put him through nuke school as long as he has a year of calc and physics, which is usually good enough to get the program manager at NPS for technical masters to waive the undergrad requirements.