re: What prevents Vanderbilt from competing in Football using Stanford's model?

3 big reasons.

Different conference - While the PAC12 is getting better, it's still not the SEC. Vandy is competing in the best conference in the country which magnifies the inherent disadvantages already in place.

Different recruiting landscape - Even at Franklin's recruiting peak (top 20 class), Vandy was still in the bottom 3rd of the conference in recruiting that year. By comparison, a top 20 class this year would rank 3 or 4 in the PAC12. Easier to win in your system in the PAC12 with a bunch of solid 3 and 4 stars.

Facilities disparity - As some have mentioned, Vandy hasn't put what is sorely needed into facilities. Franklin had to twist our AD's arm just to get the indoor practice facility and was trying to get stadium upgrades for our dump of a stadium. This facilities disparity is a big negative when recruiting against other SEC schools with much better facilities.