Here are my thoughts on why I should be following those mantras, hopefully someone will be able to point out any floors in my reasoning.

1. Don't go in with implied odds type hands against a pot which is already being 3bet if you're out of position, I'm going to be facing more betting on the flop.
I only have an 11.8% chance of flopping trips or quads when holding a pair, and a 10.4% chance of flopping an OESD from two S/C. So S/C are definately not worth playing as I only have a 10% chance of flopping the potential to draw to a winning hand, and then it's very likely I'm not going to get the chance to draw to that hand as I'll be facing more betting on the flop. The PP's fair better but still if I'm facing a 3bet pot, I'll be putting at least about .12 in preflop which means the effective stack in the pot needs to be atleast 15x this amount according to Rentons effective stack advice - I think i might have the odds in the effective stack sometimes, but I'm sure there's something I'm missing which'll complete the reasoning here.

2. If I flop a monster bet half pot, don't slowplay it.
Not as sure on this as I used to be of the mentality of being worried of scaring people out of the pot and still am slightly. I think the concept behind this is maximising value and if I start betting on the flop I've got more streets to get value in. I guess this must be more ev than hoping the turn would give the others in the pot a chance to connect and then make it more likely that they'll play back - which is basically what I was doing if I think back to my old thinking on this.

3. Watch out for check or minraises, read it as a sign of strength not weakness.
Not too sure about the reasoning behind this, but you mention this is more learnt from experience so I'll just take this for granted now.

4. Don't chase ever.. I know this but it's still creeping into my game. Don't chase
.

Poker is a long term game, If the pot is laying you the correct price to continue and you do, in the long run you'll profit. If you try to cling onto a hand against unfavourable odds in the long term you will lose money, regardless of if you win the hand or not. This is why it's so important never to stay in a hand if you're not getting the right odds.

5. Tighten up late limping range.
I think the idea here is that the cards I play preflop are like my investment. I'm investing my chips in them, I want my investments in sound stock. The higher the % of the card strength the better it is as stock. For now I don't need to get fancy so just need to play high stock cards.

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Thanks for getting me to think about those rules in more detail a500. If there are any holes in my thinking (which I'm sure there are) or any complete misunderstandings I'd love to hear them.

- thanks again everyone for all your feedback, Gary.