Don't shoot from the hip as is the habit of the BNP fan boys like you. Take a look here:
The BAL took over in 2008. Check out that sexy red line on the graph. So how is it that the economy was doing much better when the BNP was in power as you have mentioned? It started going downhill instead since 2006 and inflation zoomed under the BNP. They were concentrating more on fundamentalism and encouraging the Mullah brigade and busy fanning communalism and sectarian violence for political gains instead of concentrating on the economy. Period!
Saifur Rahman was the Finance Minister of Bamgladesh during the last BNP term. He is regarded as the best economic brain of the country. BNP has mismanaged many things, but it was Saifur Rahman's policies that saved the country from being ruined by some self-centered elements within BNP.
You have put forward a very weak logic to prove that AL in power is the only criteria that has propelled Bangladesh to success. I would not debate many of AL successes, though. A small country with a big population and void of natural resources needs a very long time indeed to accumulate monetary CAPITAL, this you will have to understand. BD lacked this important component, because in the beginning BD had nothing to sell abroad in the 1970s. Jute had already lost is glitter in the face of headon competition with chemical fiber.
BD started with a few hundred million dollars of yearly export. Then a few companies/individuals started to sew clothes in makeshift workshops. This stitching of garments has mushroomed gradually to a mammoth industry that is propelling the economy of the country. Remittances from BD citizens working abroad have also added new muscles to the economy. With it add also our home produced natural gas. Just by luck BD did not have to import a big q'ty of fuel because of the presence of gas.
You have to understand human effort is an essential component of our growth. We did not stop working hard because of bad political climate created by BNP or AL. Both these parties did/doing bad as well as good things. Yesterday, BNP was heavily criticized for nepotism and corruption. Today, it is the turn of AL. However, read the information below to know that GDP was also growing fast during BNP time. Click the link below to see the chart and know what were the growths during BNP time. Where did you get your graph? Hope it is not fabricated.
Bangladesh GDP Growth Rate
Bangladesh GDP Growth Rate:
The Gross Domestic Product (GDP) in Bangladesh expanded 6.30 percent in 2011/2012 fiscal year. Historically, from 1994 until 2012, Bangladesh GDP Growth Rate averaged 5.6 Percent reaching an all time high of 6.7 Percent in June of 2011 and a record low of 4.1 Percent in June of 1994. The Gross Domestic Product (GDP) growth rate provides an aggregated measure of changes in value of the goods and services produced by an economy.
Bangladesh is considered as a developing economy which has recorded GDP growth above 5% during the last few years. Microcredit has been a major driver of economic development in Bangladesh and although three fifths of Bangladeshis are employed in the agriculture sector, three quarters of exports revenues come from garment industry. The biggest obstacles to sustainable development in Bangladesh are overpopulation, poor infrastructure, corruption, political instability and a slow implementation of economic reforms. This page includes a chart with historical data for Bangladesh GDP Growth Rate.
As long as you guys don't pretend to be brain dead and are doing it on purpose, I have no complaints, al all! 
