No apologies required. Primary reason for suggesting the Yongnou option is because the 600EX-RT was mentioned by the OP as the speedlite they plan on buying.
I agree that the YN-622 offers a lot of options. However, for ETTL capabilities they must confirm to the Canon ETTL proprietary optical triggering technology. the 600 system is a newer version which Yongnou is making more affordable.
I disagree about using manual speedlites are the "best" way to learn about using strobes. Its does require that one learn about power, distance, aperture and ISO. However, it also means one has to have studied, practiced and gotten comfortable with all these elements and how they interact before going out to make pictures using speedlites. ETTL on the other hand, permits one to put the speedlite on a stand, put the ETTL trigger in the hot shoe and start taking pictures. Then learning how to improve and control speedlite as a creative addition by learning about how distance, power, aperture and ISO work together with ambient light to illuminate the subject.
Sometimes I think those who started speedliting with ETTL and then discovered the creative options available with manual control are the ones that say one should start with manual. While, on the other hand, those of us that learned strobe lighting before ETTL was available and now have it, including Flash Exposure Compensation and Exposure Compensation available, are happy to rely on it because we know it can get the job done with a lot less effort. Especially when applying our knowledge and experience.
Don't rush to judgement.
The only way to master speedliting is to practice and practice, both ETTL and manual. They are really just two paths to the same objective. Both work, both require knowledge, experience and practice to work well getting the picture one envisions.