Brian_Dromey
I would have to argue with you that the train is a better option to/from Leeds - its an alternative but not necessarily better.
Now that BMI have scrapped the fuel surcharge on domestic flights ex Heathrow it makes them more competitive (sometimes cheaper) on price.
You can check through (if this is being offered on BMI to LHR then LHR onwards with BA or anyone else where a through booking is made) which avoids having to be there two hours before and the hassle of re-checking in/going through security for your onward flight.
Although for your departure from Leeds you have to check in which takes time when you could be sat on a train on your way - i would rather have the leisure time of looking in the shops/grabbing something to eat etc rather than being stuck on a train where your not always guaranteed a seat.
Also if you are getting an onward connection, if your going by train to heathrow it is a major pain because you get to Kings Cross and then either take the tube all the way to Heathrow (which is a nightmare), a taxi is not cost effective, or you take the tube to paddington to catch the heathrow express (again not cheap) or heathrow connect service - which minimum you would need to allow over an hour to transfer Kings Cross to Heahrow.
The only point it might be quicker is if your only going to Heathrow to go to Central London or if your only travelling from London to go to Leeds and havent flown into London from anywhere else (i.e you originate in Central London) - doesnt mean it will be cheaper or less hassle due to availability of seats - and like me i live in Reading so to get to Kings Cross takes an hour and costs me upwards of £35 anyway by train from Reading.
Its the same if your flying to MME also (which i do regularly over driving or going by train - as 95% of the time BMI is cheaper and quicker)