Calculate SPR -> consult chart -> take action = doing it wrong.

The one thing that struck me about the SPR coverage in PNL as powerful is not the rule of thumb (SPR of 4 with TPTK is often good enough to stack off) it's the stuff about how to calculate target SPRs against individual opponents and how against some opponents TPTK is only good enough to stack off with an SPR of 2 and against others it's good enough to stack off with an SPR of 7 or higher. It's these individual SPRs that underline that what SPR is only thought a useful tool if you can FIRST put your opponent on a range, consider his playing tendencies and then ask yourself - all things considered, am I +EV against his stack off range just getting it all in from here.

My SPR is <SPR>. Fuck that, who cares. What is your TARGET SPR for this situation and how do you arrive at it? Range range range, playing tendencies, reads, exploitable behaviour.

While you could argue that the book doesn't explain particularly well how to calculate a target SPR beyond a bit of vagueness about how experience helps if the content of the book is stringently digested I think it's obvious that the authors underline the importance of calculating an appropriate target SPR over knowing some rule of thumb numbers. It's just that the part that is explained clearly and easy to understand is the least valuable aspect of it.

So basically my first read was like this:
1) Ok, rule of thumb for TPTK is an SPR of 4 is good enough to commit and stack off.
2) That number should be modified based on player tendencies and reads, which has to do with ranges and lots of more complicated stuff that I don't get and could in a specific situation be as low as 2 or higher than 7.
3) That's too fucking complicated, I'll just use 4 and hope I'm not too wrong too often.
4) Forget all about the target SPR and the complexities that this was supposed to INTRODUCE me to

So yeah, if you just use SPR casually in a sentence there's a 90+% chance that you are using it with a superficial understanding of the concept in a way that if you back it with money will be found to be misapplied and just plain old wrong.

This is not to say SPR cannot be used correctly, but I think it's perfectly true that it's more often used wrong and seen to be used wrong than used right. Even when used correctly it sort of makes itself superfluous as ranges, playing tendencies and pot and stack sizes sort of cover the whole thing anyway.

In a sense SPR is as useful as the 15x (or 20x or 25x) rule for calling with pocket pairs to make a set. Any implied odds call is only justified if you ACTUALLY HAVE IMPLIED ODDS - it presupposes that your opponent is of a type who is likely to pay you off (with his whole stack no less) if you hit your hand. What if he'll never pay you off? Do you then have implied odds? It's like saying that this hand isn't good enough to call, but given a bit of fold equity it's good enough to raise, ignoring that in the present case we have zero fold equity. As any tool you need to understand how to apply it, but much more crucially you need to figure out WHEN to apply it, as applying it at the wrong time can be a costly mistake.