Progression ending in viiº7/vi - I - Question about it

Hello my friends😀

I'm wondering how common is this. Is it something that you see frequently?

The fact is that it sounds good, at least to me.:)
My interpretation on why this sounds good is because the sec. dim chord base is the the relative minor scale of the tonic of the progression (the I in the progression) that, as you know, shares the same key signature. 
Am I thinking correctly?