Disposable lens?

Minolta MD ZOOM 75-150 2 times view angle adjustable lens is now under construction to adopt onto Canon EOS bayonet mount and complicated construction design makes it difficult to establish infinity focusing position a bit. The designing are different from the former modification on MD 35-105 and 35-70, it would be available safe if it is done orderly step by step, because the lens had been assembled in the factory it would be disassembled and re-assembled. However conditionally that irreversible constructive methods had not been introduced such as engineering plastic barrel and molding shrink fitting invited in latest MD models. There would be no way to disassemble for cleaning maintenance. It is the result of pandering to the distribution of disposable economy, is it a correct way to apply such a principle on lens production, though the producing company says the purpose of introducing is nothing but for weight reduction setting to a cover the fact? I don't agree with the opinion and this is why I prefer maintainable  MC generation to later disposable MD lenses if the weight of them are lighter and easy to carry about. This lens with relatively low view angle adjustable ZOOM lens would play a good new hopeful world in telephoto shooting.