Backbone, you say?
GSP avoided fighting Alves and Hardy in the striking realm. The same goes for his bouts with Penn (once he was tagged with a couple shots). In his rematch with Koscheck, GSP knew he wasn't going to be able to takedown Josh multiple times and he was aware of Koscheck's mid-tier/average stand up, so GSP played it safe and he employed the jab for five entire rounds. GSP followed the same formula for the Shields bout.
I didn't mention the Alves or Hardy GSP bouts because they aren't as good examples of backbone with a gameplan, however in regards to Alves & Hardy, both are strikers with limited grappling. Their best chance of winning was on the feet. While GSP is talented enough to have stood with both, he removed their chances of winning completely by putting both on their back & beating them up for 5 rounds.
Your exactly right with the takedown issue with Koscheck, he knew taking him down wouldn't be as easy as it was the first time & this time Koscheck was coming in with slightly better hands & KO power, so he completely outboxed Koscheck for 5 rounds & used his striking to take Koscheck down 2 or 3 times. He didn't run from Koscheck's power or pressure, he used his jab to make Koscheck think twice about everything he did.. and in turn he hit him with so many he destroyed Koscheck's face.
As for BJ Penn, come on man, GSP had him all day he picked him apart on the feet & on the ground on both occassions.
The GSP/Shields matchup was a poor performance & poor display of his skills, he had far superior striking to Shields who was less of a threat than Koscheck standing & he wasn't half as effective as he had been against Koscheck.
Jon Jones wanted nothing to do with Rampage standing up because of his deficiencies, but the reach advantage was overwhelming. Trust me, after being outboxed by O'Brien and rocked by Gavao, the last thing Jones wants to do is get into a slugfest with any heavyhitter.
And yet, he stood with Rampage for 3 1/2 rounds..
Jones had an excellent gameplan to deal with Rampage's striking. He used varying leg kicks to stop Rampage closing the distance significantly & when Jones did attack he exclusively threw straights & jabs, no hooks as Rampage is at his strongest when he rolls off an opponents hook.
He didn't run from Rampage or constantly backpedal for the entier bout like Condit did against Diaz even though Quinton was walking him down most of the time much like Diaz does.