He was incapable of reading one classic without relating it to another — in his edition of Chapman's Homer he scrawled lines he preferred from Pope's Homer — or else contemplating how he himself would render the same material. —Source
Is this usage the same as just "or"? Why did he add "else" here? I would like a native speaker's opinion.
Does this mean "he couldn't read Homer with just one translation. He need another translation and he couldn't read the original so he couldn't translate by himself."