The thing that happens now  is that we're using the bar here for this 4th string, so for the regular major chord, we've just got the thickest string,  and the thinnest two strings played by the bar, so it can be round a bit,  you know, that's not really touching these middle strings,  but now, once the little finger has come off, you have to be really thinking  of the pressure there in the the middle part of that 1st finger. 