I have been making a hand and all of a sudden the file size has increased from 2Mb up to 12Mb.
I have now found that it has to do with something in the channel box.
The object is called 'polyToSubd1', below it has 'SHAPES', and under shapes instead of one item there are three.
Under the 2nd 'polyToSubdShape5HistPoly' there are 22 inputs saying 'polyBlindData1' through to 22, but I do not know how to delete them.
I presume that all of this is causing my huge file and Maya acting slowly.
I hope this will make sense to someone.