Missing the point a bit though. The fact is that we do have the aforementioned strikers on the wage-bill so unless Lambert is going to get rid of a couple of them, no new strikers should be added and he should be pragmatic enough to work with what he has. Obviously though, 'Lambert' and 'pragmatism' are words that you will seldom find in the same sentence.
Also, what about when Benteke and Kozak return to fitness? We'll basically have a third-choice striker on biggish (by our standards) wages* that could be better used elsewhere. Not to mention that Bendtner is the sort of player who will instantly kick up a fuss about it also.
*Anyone who thinks Bendtner will come here for less than something like £25k/w (if that) is deluded.
Let's assume Bendtner is actually an alright player and we get him on £40k/wk (not sure what he'd want, but I'd assume he wants first team football more than a wedge - others have stated otherwise though, so...).
We're paying this extra £40k/wk for a season before Darren "60k+/wk" Bent leaves the club. Or, we're paying £2m for a player (again, assumed 40k/wk) then "saving" £2m over 2 further seasons compared to having Darren Bent around. He costs us "nothing" for 3 seasons.
(As you say, though, no idea what he'd want - it'll be more than £25k/wk though).