They both had interesting and legitimate points of view, the length of their responses to one another are too long to address here. So, as my mother used to say," I'll add my two cents and its quite simple.
All musicians can benefit from using the metronome, what matters is how you use it. I'm also of the opinion that many musicians are never taught to use the metronome properly. The instrument is there to give you a time reference, It is not a master that you should become a slave to.
Musical extremism seems to be the problem. There are too many musicians with bad time who won't use a metronome at all to players who measure every thing to the last sixty fourth. Learning to hear the space between the notes is what metronome practice is all about. If you use a basic setting of quarter notes, it will set you on the course of what Peter Erskine calls " Time Awareness".
If you have time issues the quarter note will provide the foundation. you will also begin to hear where the subdivisions fall. This will give you the awareness that you need. A metronome can't help you groove or swing. Thats up to the individual player and how he or she interprets the beat.
The issue of groove comes up often when discussing the metronome. A groove can't happen in a vacuum it can only occur with other musicians because it is a collective process. A musician can certainly aid the process by developing their time.
I've written a lot of this stuff in various posts before and I repeat it because the musical environment has changed and the metronome debate still continues. Musicians have to play with a click or a sequenced track on some gigs and you are going to have a rough time if you never worked with a metronome.
Good fundamentals work every time. Developing a solid rhythmic foundation will make you a better player and like it or not, the proper use of the metronome can get you there.
The Groove continues...