The third major offensive item is where the real fun begins! By this point in the game, any items that the enemy tank itemizes begins to decrease in effective against offensive gains -- now, you should be able to increase kill time on tanks by building additional items. We'll assume in this example that Cho'Gathhasn't been getting too many kills in teamfights, but has managed to buy a new Glacial Shroud for himself. Additionally, both Caitlyn and Cho have managed to reach level 18. As you can see above, the IE-PD-BotRK combination gets you decently strong stats -- not as strong as a pure offensive Last Whisper build, but enough to justify the slightly reduced damage for extra sustain through lifesteal. Now, let's take a step back. If we take a Blade of the Ruined King as our first item, it stays relevant in damage to an Infinity Edge up to the 10k price point despite the fact that it gives lifesteal. It creates some interesting possibilities -- if there are multiple tanks that are stacking Warmog's to stay tanky in teamfights, it might actually be worth it if you can anticipate this and rush BotRK. Take what you will from this graph, but to me, BotRK is definitely looking a hell of a lot more viable as an AD Carry item rather than being the noob trap it was last patch.
Since I am Captain Hindsight: Gentleman Gustaf would like to point out that the IE-PD-BT combination will give you a kill time of 12.63s, which is approximately the same time as the IE-PD-BotRK combination.