Let's set aside for the moment the facts that no one who was part of the royal inner circle ever accused Richard of killing his nephews & the fact that Henry VII flipped his wig whenever a pretender appeared on the scene. Also, please consider that if you are going to off someone, you want to do it on the quiet, with as few others involved as possible, and most importantly, as quickly as possible to avoid detection. Keep all this percolating in the back of your mind for the moment.
Also, please keep in mind that the bones found in 1674 are not the only set of bones found within the Tower. "Too Many Bones in the Tower" & "Bones, Burials, & Bunkum" provide more details. These sites, along with the Center for Thomas More Studies, all cited below, are where I got my information for this article. They are all very interesting reads & I recommend them.
According to Thomas More, 8 men, besides Richard, were part of the conspiracy to murder his nephews: John Green, James & William Tyrell, Robert Brackenbury, Miles Forest, John Dighton, an unnamed priest associated with Brackenbury, & an unnamed page who somehow knew what Richard wanted to do.
Already, we have a problem. That's an awful lot of people to have in the know about a secret murder, don't you think? How widespread was this conspiracy, if Richard's page supposedly knew enough about it to suggest a couple of hit men? And if it was this widespread, why wasn't Elizabeth Woodville screaming her head off about it? Most importantly, why didn't Henry Tudor use this information to whip up opposition to Richard & use it as justification for usurping the throne? Because, let's call brass tacks brass tacks: Henry had a piss-poor claim to the throne on his own, so much so that even claiming it by right of conquest wasn't enough. He had to marry Edward IV's daughter to seal the deal, & even then, he still faced challenges. (Yes yes yes, I know he SAID he would marry her, but after Bosworth, he took his damn time going about it & had to be "reminded." Even after waiting to see that she wasn't pregnant by Richard. Creep.)
Back to More.
More wrote that the boys were murdered, buried at the foot of a staircase, "suitably deep" & under a great heap of stones." James Tyrell then rides off to Richard, who is on his way to Gloucester, to tell him the news. Upon hearing the news, Richard is happy but says the bodies need to be moved as they are not in a place proper for burial of a king's sons. So the priest goes back to the Tower, digs up the bodies & takes them to someplace unknown to anyone but himself. Keep in mind that all of this takes place in one night & that presumably nothing was out of place the next morning when the day shift arrived for work. And we're also going to have to presume that the priest worked alone.
Do I have to state the obvious that James Tyrell did not rush to Richard on the road to Gloucester in a shiny red sports car & that the men doing the grunt work of busting up a staircase, or the foot of one, did not use power tools to blast through stone & cement? Of course I do, because I'm a smart ass.
More ends his account of this event by telling us his information came from Dighton & James Tyrell, under torture (but conveniently leaves out that this happened in 1501 & 1502, decades later), & adds that the bodies of the Princes were "God knows where."
IF More isn't making this up out of whole cloth (I'm being polite), the Princes' bodies were not left at the Tower at all, but somewhere outside the Tower, in a location fitting for the sons of a king. Which, presumably, isn't the middle of the Tower yard or the moat, where other bones have been found in the Tower, or the River Thames. That place would presumably be in a church or an abbey, somewhere in a chapel or the sanctuary, & surely SOMEONE would have noticed that happening & remarked on it. (as an aside, other accounts made about the time More wrote have placed the bodies in the basement of the Wakefield Tower. Has anyone dug that up lately?)
Now let's look at the 1674 account, shall we? According to John Knight & Johann Gybbon, two skeletons were found while workmen were demolishing a staircase that led from the Royal apartments to the Chapel of St. John which is located in the White Tower itself. Knight states the bones were found 10' down, in the foundation. Please note: Gybbon & Knight state the bones were found "in" the staircase, not at the foot of the staircase. Knight also informs us that the workmen initially threw the bones into a rubbish heap along with other trash, including animal bones.
I'm not sure if the above is the actual staircase (but it's says so on the Internet so we know it's true, right?), but I have been through the White Tower a few times & the staircases there are circular, stone ones, not wooden ones where all you need to do is pry loose a few boards, stuff something in (like, say, a couple of bodies), seal up with a couple of nails & a hammer, & then sit around reading the paper, trying to look innocent so the day shift won't think anything is amiss & wonder what that smell is.
Nope, they would have had to dig through stone & cement, in the Tower that was initially a military installation, built to withstand bombardment & invasion. It was not your random, creaky, rickety old wooden staircase, like the kind you would find at Grandma's house. Busting though stone & cement & digging 10' down into a foundation is a noisy, messy, time-consuming affair today. It is not something 2 men working with hand-tools can do in 8 hours & it is also not a job that can be started, covered up during the day, & then worked on the next night without someone noticing. Either that, or we have to believe that a hole looking suspiciously like a grave was dug under a staircase that had been broken apart & NO ONE thought "Oh bother, can't use these stairs. Wonder what that's for & oh by the way, where are Edward V & his brother?"
Seriously, people. Take your blinders off & use your heads for something besides decoration & look at this logically. More is talking out of his hat, here.
Let's go back to what I told you to keep at the back of your mind for the moment: It would have taken too many men too long to have put the bodies of Edward V & his brother where the bones were located (& initially discarded) in 1674. Also, More has way too many men in on the conspiracy; surely ONE of them said something to someone at some point along the way, but only James Tyrell & Dighton did, and that was under torture, decades later. And why go through all the trouble of busting up a stone staircase (or the foot of it), when there's a handy moat & a river nearby to dump the bodies in, especially if you only have one night to complete your task? Or, if that's not a satisfying place given these are royal bodies you're trying to hide, wouldn't it be easier to stuff them into bags & take them out by wagon to a suitable spot?
Were Edward V & Richard, Duke of York murdered or were they smuggled out of the Tower & England? We will probably never know. But I can say this: More's account simply makes no sense when you take it apart & really look at it. Can we finally bury that account somewhere & stop using it as "proof" of what happened?
Sources: More's History of Richard III http://www.thomasmorestudies.org/docs/Richard.pdf, specifically pages 75-79.
"Too Many Bones" by Becky Adjoran http://medievalaccommodation.com/medieval-britain/LMB%20Pages/Pages-a-d/too_many_bones_in_the_tower.htm
"Bones, Burials, & Bunkum" by Donald Maclachlan http://home.cogeco.ca/~richardiii/bunkum.html