Many genes in both prokaryotes and eukaryotes contain many sequences that can cause pauses or prematurely terminate transcription. Nevertheless, the genes within a cell normally produces multiple RNAs that may be thousands of nucleotides long without pausing or terminating prematurely. However, when a single round of transcription occurs on such templates in a test tube, RNA synthesis is frequently interrupted by pauses and premature terminations, which reduces the transcriptional rate and frequently shorten the length of the mRNA molecules. Most pauses and terminations occur when RNA polymerase temporarily backtracks for one or two nucleotides along the DNA. Experimental findings have demonstrated that most transcriptional delays and premature terminations disappear if several RNA polymerases are transcribing the DNA simultaneously. Propose an explanation for faster transcription and longer mRNA when the template DNA is being transcribed by multiple RNA polymerases.