This is what I don't get:
With a good OC (i.e. the OC version of HCSS as DC), how many more games do we win? How much more interesting are our games (from a SU fan perspective)? How much money does that translate into? What's the going rate for a good OC? 1-1.5 million? How much will we have to pay to buyout a current coach? Will we really not see a positive return on investment if we invest in a good OC? A&M got an increase in donations to the tune of $200 million when Manziel won the Heisman. Will we really not get another $2-3 million in revenue from donations, ticket sales, merchandise sales, etc. combined moving from a 3-9 team to a top 25 (possibly top 15) team? I find that incredibly hard to believe. Going cheap and losing seems more expensive to me.
I realize we have more problems than just coaching (i.e. talent, game day environment, player development, etc.), but a big fish OC will solve many of those problems, either directly or indirectly.
A good OC wins games, which keeps HCSS as the HC, and thus establishes an increased degree of coaching stability to both the offensive and defensive sides of the ball.