Another Dell advert ...I mean workshop
Yes the small print says "series of Oracle DBA workshop articles in association with Dell Software." but if they're allegedly workshops rather than adverts then really it would be prudent to mention other alternatives. If it hurts too much to mention competition (whether free or paid for) then why not at least mention that Oracle's own OEM could be used for all the instances of "..such as Toad" was used.
As it is the whole series just stinks of desperate attempts by Dell to (re-)sell Toad. Which devalues the series which does contain valid pointers for less experienced Oracle DBAs.