> For a rigid road bike aluminum can definitely be made stronger and lighter,

Absolutely. What I meant was that while an aluminum bike frame can be lighter than steel, it's not as much lighter than steel than you'd expect. Steel bike frames tend to be only ~15% heavier than aluminum, not 50%.

Personally I bought a steel road because the difference in weight vs the aluminum alternative was small enough that I decided to go with the bike that looked nicer, and would last longer. Besides, I could use to lose a lot more weight than any bike ever could...

> I could use to lose a lot more weight than any bike ever could...

Get a child trailer and load it up with groceries or cement! i tried it, the results are.. Surprising