On my behalf I was not cynical but in my opinion there are better alternatives for hobby mixers to control low end than just adding a subwoofer. It will not give you immediately better results because you'll have to learn mixing with subwoofer first. Subwoofer is almost useless until you have a good, well treated room with enough space; you can hear if there is "a lot of" or "not so much" low end but you're not able to hear anything accurately.
Of course it's not possible to make a comprehensive presentation of low end mixing in one post. That's why discussion continued here; to give alternative opinions and points of view.
It's not just a blog post. It's Cakewalk's blog post! It gets more attention than some anonymous blogs from unknown sources. Cakewalk means recording knowledge and professionalism.
The next blog post subject could be room treatment and setting up monitoring system. It has far more influence on the mixes than any plugin you use. New brickwall limiter or $$L compressor may improve your sound in the last 0.1 dB but a few acoustic panels in the right spots may improve mixes 9 dB.