To seal, or not to seal...

Hi y'all,
I have purchased a couple of bottles of Tru-oil, and plan to get into finishing a couple of projects.
Please feel free to view this attached link, to Ken Parker applying a sealing coat before applying Tru-oil.
It's part 1 of a series on finishing an archtop style guitar. https://www.youtube.com/watch?v=1MLVfjwNsEM
Is the consensus that a sealing coat is required? I'm not that interested in mixing up epoxy, as he does here, but maybe another option is readily available, and worthwhile?

Cheers, Ian.