"tightened up my play" .... idk.. 'it depends'.
There's a bunch of stuff to consider in later stage Tournament play... as a bigstack (depending on table & eff. stack sizes, image, etc.).. you might want to be taking stabs regularly & backing off if played back at... hoping to be played back at when you've obv. got good. BUT.. who knows? 'tightening up my play' is too broad of an explanation of how to play in spots.
For sure though... once you lose a big chunk of your stack, just 're-adjust' your play based on your stack size, the stacks of others on your table, the types of players on your table, etc. etc. etc. Look for spots.
I see lots of players who figure because they've got a good stack they're guaranteed a decent % of the prizepool & then go & spew & punt off their remaining stack after takin' a beat or losing a large pot. You just have to 'let it go'... move on... make best possible plays based on current circumstances/variables. It's not over til' it's over.
gl in the next one!