Hmm.. The fact that the lyrics are ridiculusly funny (moreso when sung in this manner) doesn't mean the song is not nice. I like the orchestration and the performance a lot. And I do appreciate songs with a bit of sarcasm, that can be read at a second (deeper) level.

However since you put it side by side with Bitter Wine, which is a straightforward love/nostalgia ballad, I am not sure if you have understood the lyrics of Backdoor To Heaven.

Btw Bitter Wine is definetely on my top 5 bon jovi list. And it does have a clear sexual reference also, which is censored in many editions of the lyrics: "giving me head in that creeky old bed.." Also quite hilarious, but does not break the general serious melancholy of the song. Very nice :-)