"I have to ask, why the heck does it matter 
if 
someone shoots their wad all at once and bids 
their max from the get-go or bids in itty bitty 
increments across the life of the auction?"

On ebay, there is not too much difference, 
except the constant whining of nibblers on the 
eBay forums about snipers. -_-  Otherwise, heck, 
more nibblers = lower prices for me. ;)

On YJ, it does matter because of what I said 
previously.. I've seen auctions extended 30+ 
minutes because the same 2 bidders kept nipping 
at each other, or because 1 bidder keeps nipping 
at the high bidder over and over.  If they bid 
once, the auction would not be extended at all.  
Its just a pet peeve of mine.  :)  And also, by 
nipping away and extending the auction, it 
leaves the possibility open that a 3rd party 
discovers the auction for the first time and 
decides to bid, when otherwise the auction would 
have already been over.