Let me rephrase this. Sorry for being brash.

Taking 1 point in Tides of Blood decreases your DPS, and only makes you weaker. The amount of E spam it takes to equate to the same amount of health lost from your W is roughly 8. Sanguine Pool takes 20% of your current health to use, and most of the time you don't have that much health to spare; defeating the purpose of high ranks in it. It barely does ****ed up damage since the nerfs (not in a good way), and it's just overall not a great spell to max.

Maxing Tides of Blood second encourages high-risk high-reward gameplay; and thats' the pinnacle of Vladimir. If you don't risk, you don't win.

Also, Flat AP runes work better, because you don't need the minimal amount of AP it provides you with later in the game. Scaling/Flat runes fall off at around 9. That's when Vladimir is at his best, and even at that; the increases from the Scaling runes is so minimal its not worth it. You want your eggs to be in the basket that matters. Flat runes ensure Vladimir a steady early game, and pave the road to victory for a phenomenal late game. Taking scaling runes encourages passive gameplay, which is not what Vladimir is about.
Additionally, Spell Penetration ( Sorcerer's Shoes) boots aren't very viable on Vladimir anymore. They were great back when he had 25 HP per AP as a passive, and his Q was a 3 second cooldown, but they really fall off now. Taking CDR boots gives you more sustain in lane+team fights (more Q's= more HP=More damage= More kills= mo' money), in opposition to the Spell Penetration boots which barely mitigate any of their damage. If you want penetration, get a Void Staff. There are better buys for shoes. You COULD swap out Spen boots for CDR Boots later in the game if you wanted to go for a haunting guise/sorc boot rush to just decimate all of their MR early, but it's not very viable.

Feel free to add me on skype or add me in game if you want to discuss Vladimir
Skype/IGN: Incendiax