The main difference between TSC & TSSC is that the TSSC does not contain main and secondary options, there are number of other relatively minor differences also e.g no risk / early warning register (but still an obligation to early warn) and the requirement for a contractor’s plan is optional. The short contract can work well if the service is relatively simple and / or is only being provided to a few properties, for example I’ve used it for lift maintenance services and office cleaning. More complex services i.e. multi-site, bundled services carried out over long periods of time should be procured with the TSC.
Capital works projects can be instructed using the Task Order procedure but you don’t have the same level of controls or flexibility with this as you would have in the ECC / ECSC so it’s really only suitable for low value, low risk works.