Ha ha! I can't even remember what I wrote :-) There is always the chance that it was rubbish ;-)
As you say, waiting until there is an indent it the best way to go. Otherwise it depends a lot on the size of the thing you are spinning (larger things will have more torque and will spin more easily than smaller things). I think the key here is that it doesn't really matter when you declare FP to have happened -- as long as its consistent. You can adjust your multiplier to match.
But you might be wondering, how do you follow a recipe if your FP is different than the author's FP (and therefore requiring a different multiplier)? For me, I think you need to get into the logic of the recipe, rather than following the directions. Quite a few people make cheese with the idea that there is only one point where they would like to cut the curds. But this is not really the case for traditional cheese making. For some cheeses, you want to cut the curd when it is less firm and for others you want to cut it when it is more firm. This is what the flocculation time and multiplier are describing.
The flocculation time just describes how fast the curd is forming. It's probably not the case that it's linear, but for the part of the curve that we are interested in, we can pretend that it is. The multipler describes how hard you want the curd to be. So cutting the curd at a multiplier of 1.6 is very sloppy, 2.5 is about normal, 3.0 is fairly hard and above that is super hard. In some respects it doesn't matter how fast the flocculation time is: we are cutting the curd at the desired firmness no matter what. However the curd continues to firm up even after we cut it. So if your flocculation time is 5 minutes, your multiplier is 3, that gives you 15 minutes coagulation time. If you do a short 15 minute stir, then that's a total of 6x the flocc time in the vat. If your flocculation time is 15 minute and everything else is the same, then you are in the vat for 50 minutes -- only 4x the flocc time. So likely the curds with the short flocc time will retain much more whey than the long flocc time, even though the stirring time was the same and we cut them at the same multiplier.
Also, keep in mind that the curds are acidifying the whole time. So with the short flocc time, we're in the vat for 30 minutes and with the long flocc time, we're in the vat for 60 minutes. The pH at draining will be *completely different*. This can totally change how the cheese drains and even affect the final pH if you are not adjusting for that difference. You could make a very different cheese if you do everything exactly the same and only change the flocculation time.
When I'm making cheese, I kind of have in mind that there are pH targets and moisture targets at various points. Your goal is to do what you need to in order to hit those targets. The recipe is less a series of steps you have to follow and more a strategic plan for how to tackle the problem. When I'm looking at a recipe, I'm thinking, "What are they trying to accomplish and why". That's quite tricky sometimes and requires more knowledge and experience than I can write in a post. In fact, I'm still quite deficient in that area anyway. But slowly over time, I try to pick up more puzzle pieces and figure out how they work.
But after having typed all that... yes, I think your plan is correct :-) Try to adjust the rennet to hit your targets. Keep good notes and keep adjusting.
