Line BORING is not usually done or required, unless fitting a different set of main caps on a Block.
Line HONING is commonly performed to adjust main bearing Clrc's or straighten or bring back main Bores "round", that have subjected to different clamp loads.... ie; changing from stock Bolts to Studs.

We Line Hone everything, just a matter of procedure,because everythibg is "off" the mains and we have to square the Block Decks as well as correct the Bores perpendicular to the mains.
and NO... unless you are a dork cutting .010" off the main caps because you can't line hone properly, a shorter timing chain is NOT required.