Clingfilm Good Or Bad?

Ok i was talking to a guyon youtube and he said to put clingfilm over the top of the pot while the seed has not come threw the soil. Now i think this would suffocate the plant and probablt cause disease and mould in the soil. Am i wrong or is he wrong?

Yea i do that with all my seedlings now it seems to make them break thru the soil quicker but i only leave it on for a couple of days, I never thought of it promoting mould or anything so maybe someone else will shed some light on good and bad points of this!

I cover the cups with film until they break through. it is only for a few days and has not caused any problems for me.

Ok fair enough i will try this method if it will get my babies out of the soil quicker. ITs been 2 days and still no sign and planted my other 2 today .. I just thought it might have a bad effect and cause my babies to die..