Short series can make or break a team, especially if the weaker team has a very strong starting 3 pitchers.
Which is why the ChiSox can still be a tough draw even without an offense
You are right. In a 5 game series you will probably see their top pitcher twice (unless you sweep in 3) and the #2 at least once, (twice if it goes 5).
There is talk about making all the playoff series 7 games just for that reason, revenue being an underlying reason.