Just my N+1, if you can increase your intensity to 105% for a week and if it feels like your not fatiguing yourself, then I’d add 5% on to your FTP.
I’ve done this myself recently, I was finding workouts easy, wasn’t tired at the end at all. I know after past years of training what I should feel like, so I set the intensity to 105% at the start of Spanish needles and completed well… the other workout, started and finished at 108%. So this week I upped my FTP by 5% and have been completing workouts fine, in fact last night I added a bit extra during rest intervals as I have a recovery day today.
I believe I had a mixture of bad weeks and ramp and my FTP dropped some 10%, but as you say it comes back fast and who likes to ramp weekly, some will, I don’t as I feel I do bury myself with them. I more than happy to move intensity up and down and change my FTP as required. Feel after all these years I know what is right and what isn’t after doing workouts…
The end of the day I want my TSS and IF fairly accurate and by just upping intensity won’t do that, unless you alter the ftp for that one workout post, or alter before doing them.
And finally yes I do normally ramp test at the start of training blocks as the plans have it scheduled, and I’m never far out!
Hope this helps.