Hi,
Don't worry about your frames this frame has really gone through hell for 20 years and out lasted every other component on the bike. Winter road riding (salt) has done the most cosmetic damage, the paint on the aluminum is now really pealing due the white powdery corrosion of the aluminum.
Yes frame has got more flexible with age, its has done thousands of miles with me on it and I have had some big frame crunching crashes on it. I owned a 92 Raleigh Summit before the Diablo and I bent two frames, these frames are very much stronger than the Raleigh K2 tubed frames from the previous year. I am a big and powerful rider (use to throw the discus and Javelin for Hampshire) and this frame has done itself very proud indeed.
Its feels very strange going round a corner hard (on road & slicks) and you can feel the wheels doing different things as you ride over the bumps. I don't know if its the metals or the joints or both but it is too flexible for performance riding especially riding up hills. The M-Trax CroMo 1000 I am selling has so much more drive up the hills it make the Diablo feel poor. You really can feel the difference between the frames ability to transfer your pedal power in to back wheel drive.
Absolutely stunning frame and a real joy to ride and own, I will be using the frame to rebuild a 100% original spec 93 Diablo RS (apparently quite rare) and I will be taking out for gentile rides, I can't say goodbye!
Glad you like it........