Absolutely. One could make the argument, though, that many (including me) believe that expressive power and conceptual beauty is Lisp's core strength, not code maintainability or runtime performance.
Common Lisp was designed for development of large/complex applications ('applications' really means here software that is used in production) with good performance.
For example this CAD system from PTC is based on 6+ million lines of Common Lisp code and under development for two decades:
HN is fast because it is feature-barren. That's a design choice pg is free to make (and cutting features is a great way to improve performance), but not a proof of Arc/Lisp's ability to support complex applications with high-performance.
Just for the record, let's count to 100 million. And add the numbers up while we're at it.
~ $ time (echo '(do (= n 0) (for i 1 100000000 (++ n i)) prn.n (quit))' | arc)
Welcome to Racket v5.3.5.1.
Use (quit) to quit, (tl) to return here after an interrupt.
arc> 5000000050000000
real 0m28.561s
user 0m28.308s
sys 0m0.249s
----
~ $ time (echo -e 'n=0 \ni=0 \nwhile (i <= 100000000): \n n += i \n i += 1 \n\nprint(n)\n' | python3.3)
5000000050000000
real 0m30.244s
user 0m30.230s
sys 0m0.013s
It would appear to be competitive with Python on my machine on this particular task. (Also you can make it faster by dropping into Racket.)
A while loop and temporary mutable variables are definitely not the Pythonic way of doing this. More idiomatic:
$ time python -c 'print sum(xrange(100000000 + 1))'
5000000050000000
real 0m1.398s
user 0m1.383s
sys 0m0.012s
Comparison to baseline:
$ time (echo -e 'n=0 \ni=0 \nwhile (i <= 100000000): \n n += i \n i += 1 \n\nprint(n)\n' | python)
5000000050000000
real 0m33.140s
user 0m32.939s
sys 0m0.023s
I see. That is good to know; I merely chose mutating global variables in a loop because I knew how to do that in both languages. (I am not very familiar with Python.) That is not the idiomatic way to do it in Arc, either. I would normally use a recursive function, like this:
arc> (time:xloop (i 0 n 0) (if (> i 100000000) n (next (+ i 1) (+ n i))))
time: 9121 cpu: 9130 gc: 0 mem: 480 ; the times are in msec
5000000050000000
Yep! Not saying that it's impossible, just that some of the concepts that Lisp is based on make these things harder to pull off. The reason for this is that Lisp emphasizes flexibility, and the more flexible your runtime environment is, the more ways to do something, which makes it easier to have hard-to-maintain code (and harder to reason about performance, too). But it's not impossible to do with Lisp for sure.
Lisp macros also provide ways to take ugly, hand-optimized code and clean it up to provide a cleaner, friendlier interface. Like all macros, this comes at no runtime cost (since all macros have been fully expanded by this point).
Actually, it's not any harder to write maintainable code in Arc. In many ways, it's much easier, because you write your program as a set of parts which fit together like an arch.
For example this CAD system from PTC is based on 6+ million lines of Common Lisp code and under development for two decades:
http://www.ptc.com/product/creo/direct