I like the glueing of the magnet as a fix for dried glue letting go as the original glue has aged poorly. The dynamat is more a psychological fix than a huge improvement. Yes, a speaker basket rings when tapped as an unmounted entity, but once it is mounted it no longer rings at the level it did, as it becomes part of the baffle structure and the resonance is now that of the full baffle, not an individual piece of thin metal. A channel beam is like a tuning fork by itself until it gets bolted to a stiffer structure.
I like dynamat for panels of electronics, car doors, trunk lids, etc. that tend to ring when struck, but the Polk midwoofers when mounted have a lower tink/thud when tapped. This goes against most the modders of these speakers, but there is no frequency response graphs backing up their claims, just "if it rings, it must be damped". It shouldn't hurt to dynamat, but again no response graph ever indicated a ringing was causing a bump in the frequency response in the first place. It has just become a defacto upgrade, due to its ease of application and it does deaden the ringing of each free air speaker. If the stamped frame was really an issue, Polk would have gone with cast baskets and they still use stamped metal today in many of their more recent speakers.