From memory when I used to sell them the 'Dynatech' name was used initially for their bonded Titanium frames, although they did retain the name for a while when they evolved into being welded. The name M-Trax came very soon after, there were a few examples of the bonded construction but by then most were welded. In addition to Titanium M-Trax were also made in steel; welded, not lugs and brass.
I can see the comments about the quality of Raleigh bikes, but for my ten pence worth, when I started 40 years ago when it comes to the quality of mass market productions bikes the quality was competitive with their rivals, Dawes were probably the most similar, but even then the amount of company's manufacturing in the UK was diminishing. If I recall the likes of 'Claud Butler' and 'Holdsworth', aimed at the higher small volume sector no longer manufactured in the UK. Yes you could get far better quality, the artisan frame builders were far more common place than they are now, there will no doubt be lots of forum posts about those builders, the two most local to me were 'Roberts' and 'Cliff Shrubb'. Many club riders would ride a frame from their local artisan builder; often these were of very high quality and understandably many were and still seen today as desirable works of art.
'
Mercian' still build in the traditional way in but most of the current artisan builders will weld, in part as that is the method many of the
thin modern steel tubes are designed for; these thinner lightweight tubes are often not conducive to being heated with a flame for brass and lugs. In reality the skill set is quite different. I asked 'Geoff Roberts' when he used to run the frame building classes at Enigma Bicycle works if he ever welds, he laughed, picked up one of the welding masks that the Ti welders used, faced me and said "I can barely see you Paul let alone a teeny tiny weld

"...edited for Geoff's modesty, he may have said the odd expletive in qualifying his 'NO'
Back to Raleigh, yes I have lot of affection for them and as yes my glasses may have a 'Rose tint 'to them

, but I also respect what they once were, a UK manufacturer that rivalled those anywhere in the world with a similar business model; I was proud to promote them. I still have two Raleigh bikes, both of which I still use, a Raleigh Pioneer Elite, built with lugs and brass that is about 35 years old and a Steel M-Trax that I have had about 30 years, I smiled when I found my 'I love my bike pictures'; the two of my M-Trax are a bit of a time stamp

.