If he wanted feedback it would be unwise to bid 
so high as it would just attract unwanted 
attention.

Neither would he have to use so many id's.. it 
would save a lot of time to use the id's on 
separate auctions for more feedback.

Anyway this seller obviously does not care much 
for feedback as he his id's do not last long.

It would also be very unwise for the seller to 
use the id with all his details on it if it is 
his own auction. (& also not very prudent of the 
bidder)