I've participated in this debate on other Forums.
First- there is no 'right or wrong' just what works for you.
Saying that heavy strings are a 'crutch' is a bit insulting in its implications.
Its all about tone.
Plenty of players do use light strings and light glass
slides and get good tone. Usually they are compensating with more overdriven electric guitars.The more sustain, compression and overdrive generated by the guitar, amp and effects used, the less important the gauge of strings becomes.
Damping behind the slide also can become less critical in that type of setup.
I just dont agree that because light strings and a light slide work for one players style that it is a superior method. Its just another way of doing it.
Personally, I use high action, heavy strings, heavy slides, AND overdriven compressed sustained amps and effects.
I ALWAYS get compliments on my tone.
b.