Good and bad w/ replacing stock preamp jumpers?

In the past several days I replaced the stock preamp jumpers on my integrated ($2800 retail) with aftermarket jumpers. I was told once by an audiophile he felt that removing the stock jumpers on my integrated (the amp in question was an expensive one-$5k) for aftermarket jumpers can change the tonal balance of an integrated, thus changing the designers intended sonic presentation. What are your thoughts on this? What's your experience with aftermarket jumpers? Also, aren't the preamp jumpers perfoming the same function as interconnects do between a separate preamplifier and separate power amp? And if they are, why do most of these manufacturers use cheap pieces of metal to connect an integrated's preamp to amp? This occurs even in some of the better more expensive integrateds? Why not provide a quality connection that could conceivably improve the sonics of the unit? I've read where audiophiles with integrateds routinely replace these cheap metal jumpers with a quality interconnect and gain improvements. It makes no sense that a manufacturer spends the money on R&D to build a quality integrated with quality parts and then compromises it with a poor quality connection between the preamp and amp when there is all this hubbub in audiophilia about better and more exotic interconnects that will take your system to the next level. If the quality of interconnects are considered by almost everyone in the audio world to be so vital to an audio systems performace why is the quality of the preamp jumper no less important? Or am I way off base here? Thanks for your perspective.