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This low level of beamstralhung provides several advantages, some examples of which are given below.  \begin{itemize}  \item All $\epem$ collisions are affected by initial state radiation (ISR), a microscopic QED process calculable with a great accuracy. The resulting beam-energy spectrum is therefore known with a negligible uncertainty for any physics process. In contrast, beamstrahlung is a macroscopic effect that cannot be predicted from first principles. The resulting beam-energy spectrum therefore needs to be measured in situ, with correspondingly significant statistical and systematic uncertainties. As a consequence, the measurement of observables relying on a precise beam-energy knowledge (e.g., Z or W masses, Z width, top quark mass, etc.) greatly profit of the relative  absence of beamstrahlung at TLEP. \item Cross sections with a rapid variation as a function of the centre-of-mass energy (e.g., at the Z pole, or at the WW and $\ttbar$ thresholds, as shown for example in Fig.~\ref{fig:ttbar} of Section~\ref{sec:EWSB}) are {\it (i)} larger; and {\it (ii)} calculable with very good accuracy at TLEP, leading to small statistical and systematic uncertainties.  \item The forward region of a TLEP detector is free of beamstrahlung photons, which in turn tremendously eases both the design of a luminometer and the integrated luminosity measurement.  \item The beam-related backgrounds (disrupted beams, photons, $\epem$ pairs) originating from beamstrahlung are negligible at TLEP, and so are the parasitic $\gamma\gamma$ collisions, which would otherwise lead to significant pileup in the detector, and affect the reconstruction of jets, the determination of the missing energy and the efficiency/reliability of isolation criteria.