Yes, this could work.
However, according to my own calculations you will get more bitcoins with euros when you buy at Kraken. This is because BitStamp only works in USD and you actual get their exchange rate:
https://www.bitstamp.net/api/eur_usd/ Also currently
Kraken charges 0.3% and
Stamp 0.5% at the lowest level (will be
0.35% for Kraken from 1st of September.) With a bigger amount, you will pay less fees, so with the fees and exchange rate of Stamp, you should be able to calculate the cheapest way to buy bitcoins with euro. This will be different from time to time, so make your own calculations please.
Then for the selling part I guess you could do the same calculations, but I do not have experience with that part (since I am not from US), so not sure which site is reliable and cheap. Obviously if you have to withdraw BTC from 1 exchange to another the BTC price can move too, so you should consider that too. Also consider withdrawal fees. Like BitStamp charges a
0.09% fee (minimum $15.00) on international withdrawals,
BitFinex 0.1% (min $20), etc.